c#里面students.Where(r => r.studentsID ==we studentssName)

Brad Wilson: Input Validation vs. Model Validation in ASP.NET MVC
Technologist. Agile Evangelist. Poker Player. Amateur Neologist. Metalhead. Guitar Guy. Percussion Pounder. Fire Child.
After extensive discussion among the team, we've decided to make a last-minute change to ASP.NET MVC 2 in regards to way that validation is handled. The conversation was kick-started by my
and what it does (and does not) mean. More importantly, I want to re-address the security issues I brought up in the last post, now in the context of Model Validation, to understand whether this change makes your applications more secure.
To understand what we did, let's start with where we were a couple days ago.
Input Validation
Let's start out with a sample model:
public class Contact {
public int
public string FirstName { }
public string LastName
public int
And a view:
First name: &%= Html.TextBox("FirstName") %&&br&
Last name:
&%= Html.TextBox("LastName")
&%= Html.TextBox("Age")
Finally, here is our action method:
[HttpPost]
public ActionResult Edit(int id, Contact contact) {
if (ModelState.IsValid) {
// Submit values to the database
return RedirectToAction("Index");
return View("Edit");
When your Contact object is being model-bound, we will automatically run validation. This was true in ASP.NET MVC 1.0 as well, though we didn't have a pluggable validation system so most people weren't even aware that we had any validation support. The DefaultModelBinder class had validation hooks as well as built-in support for IDataErrorInfo for validation.
In addition to validation, there are also possible model-binding errors. The two major categories of these are: (1) data which is not compatible with the destination type (f.e., submitting "dog" for an integer), and (2) not submitting any data for a value which always needs data (f.e., a non-nullable value type like integer).
These kinds of errors are handled by the model-binding system before validation even happens. In MVC 1.0, these two situations were represented by the messages "The value 'dog' is not valid." and "A value is required."
In the early MVC 2 previews, we added a pluggable validation system, and in-box we provide support for the validation attributes in System.ComponentModel.DataAnnotations (as well as backward compatibility with IDataErrorInfo, though we suggest people migrate away from that at their convenience).
The implementation in those early previews is what we would call "Input Validation". The prevailing feature of Input Validation is that we would only run the validators for properties for which there were form inputs.
Let's pretend all three of the properties of our Contact model (besides ID) now have [Required] attributes on them. With the form in the view above, if you failed to provide a value for any of those properties, you could get a validation error telling you that the field was required. Checking ModelState.IsValid is how we know if there were any model binding or validation errors.
What happens in the case where we forget to provide a text box for LastName? The model binding system will create Contact objects for you, and fill in the FirstName and Age, while the LastName will remain null. There are no validation errors for LastName, because it wasn't part of the form.
This takes some people by surprise. In an Input Validation system, the purpose of [Required] is to ensure that if the user was offered an opportunity to provide a value for the field, we'll make sure it isn't empty. But what if the user wasn't offered the chance to edit that field? Does it make sense to enforce [Required]? More importantly, what if a bad guy decided to try to "under-post" your form by leaving off the LastName field?
In short: is validation a security system? Let's look at the impact of the change we made.
Model Validation
Earlier today, we committed a change to MVC 2 that converted the validation system from Input Validation to Model Validation.
What this means is that we will always run all validators on an object, if that object had at least one value bound into it during model binding. We run the property-level validators first, and if all of those succeed, we'll run the model-level validators. In the case of our Contact object with [Required] on the editable properties, if you accidentally left off the LastName property (or a bad guy "under-posted" the form without it), the validation system would see the null LastName value and trigger the error message.
What about complex objects inside of complex objects? Let's expand our Contact object to include address information:
public class Address {
[Required] public string Street
[Required] public string City
[Required] public string State
[Required] public string ZipCode { }
public class Contact {
public int
[Required] public string
[Required] public string
[Required] public int
public Address HomeAddress { }
And let's use the same view:
First name: &%= Html.TextBox("FirstName") %&&br&
Last name:
&%= Html.TextBox("LastName")
&%= Html.TextBox("Age")
Now, when we model bind the object, we will run the following validators:
Contact.ID
Contact.FirstName
Contact.LastName
Contact.Age
Contact.HomeAddress (property-level and type-level, but not sub-properties)
Contact (type-level)
When we say we're running the "Contact.HomeAddress" validators there, what I mean is that we're running any validators that are on the property itself, or on the Address type as model-level validators. That does not include Street, City, State, or ZipCode property validators. The reason we don't "dive" into the Address object recursively is that there was nothing in the form that bound any values inside of Address.
If the HomeAddress property had a [Required] attribute on it, it would fail, because HomeAddress would be null. It's null because we didn't bind any values into HomeAddress, and therefore never manufactured a new HomeAddress object.
Let's expand our view to include just the street of the address:
First name: &%= Html.TextBox("FirstName")
Last name:
&%= Html.TextBox("LastName")
&%= Html.TextBox("Age")
&%= Html.TextBox("HomeAddress.Street") %&
Now when we validate, we'll run validators like this:
Contact.HomeAddress.Street
Contact.HomeAddress.City
Contact.HomeAddress.State
Contact.HomeAddress.Zip
Contact.HomeAddress (type-level)
Contact.ID
Contact.FirstName
Contact.LastName
Contact.Age
Contact.HomeAddress (property-level and type-level, but not sub-properties)
Contact (type-level)
Now we'll get errors about missing values for City, State, and Zip, because this time we've bound at least one value inside of HomeAddress (namely, Street).
Given this new behavior, can we consider the [Required] attribute a security feature now? The answer is, sadly, still no. Even with Model Validation instead of Input Validation, we still have the same potentially unaddressed security issues that we've always had: "under-posting" and "over-posting". Switching to Model Validation might make it easier to address "under-posting" in certain scenarios, but we're by no means completely safe yet.
The "Under-Posting" Problem
The first problem is that [Required] on non-nullable properties doesn't quite behave like you'd expect. Literally, the implementation of the [Required] attribute is that the value cannot be null. Since a non-nullable value type can never be null, the [Required] attribute doesn't actually ever say the field is invalid.
So, what's it for, then? Failing to provide a value for a non-nullable property is actually a model binding error, as I mentioned above. We query the validation system and ask it for whatever it considers to be the "required" validator for the property, so we can determine what the message should be. The "required" validator is treated specially during model binding failures on non-nullable types, so that you're not stuck with the vanilla message 'A value is required.'
The off-shoot of this is that [Required] on a non-nullable value type cannot act as a guarantee that the form included a value. If it doesn't include a value, then model binding is skipped, which means the model binding failure won't occur. Additionally, when the [Required] validator is run, it queries the value from the model -- which will contain the value-types default value, typically 0 -- and say "that's not null, everything is all good here!".
If you make the property a nullable version of the value type, say by turning "int" into "int?", you'll be able to use [Required] as a way to ensure that a value is posted.
Another anomaly with [Required] happens when you use an ORM system like LINQ to SQL or Entity Framework. Rather than using action parameter binding, you might write an edit method like this:
[HttpPost]
public ActionResult Edit(int id) {
Contact contact = dataContact.Contacts.Single(c =& c.ID == id);
if (TryUpdateModel(contact)) {
// Submit values to the database
return RedirectToAction("Index");
return View("Edit");
Now imagine that you've forgotten to provide the LastName editor, and you submit the form to the server. We happily go off to the server and retrieve the Contact object, and then attempt to update it with values from the form data. When we run the model validation system, the previous value for LastName will be intact, since there was no LastName in the form. It is presumably valid (it's in your database, after all), and so your data will go on its way, back to the database, without the LastName update.
Is "under-posting" a serious problem? It allows a bad-guy to bypass your input validation in some cases, which may cause you to pass on unexpected or invalid data upstream. Ideally, it will be caught at another layer, but only you know whether that kind of tampering could be ultimately destructive to your data. If you need to protect against it, you'll need to take additional steps to protect against it, which may include making your non-nullable values nullable and binding only against strict view-specific models.
The "Over-Posting" Problem
The other problem you could encounter is the "over-posting" problem. Let's say, for example, you have a blog and your comments are represented by this object from your ORM system:
public class Comment {
public int
{ } // Primary key
public int
{ } // Foreign key
public Blog
{ } // Foreign entity
public string Name
public string Body
public bool
Approved { }
And this is the view for the comments to be entered by users:
&%= Html.TextBox("Name") %&&br&
Comment: &%= Html.TextBox("Body") %&
The intention for comments is that they won't be approved by default. The blog owner will come along later and use the UI to approve all the non-spam comments.
What happens if the bad guy includes "Approved=true" in the form post? The model binder will happily set the Approved property to true. That's definitely not what you intended! It actually gets worse: if the bad guy guesses your entity object is called Blog, he might try posting values into fields like "Blog.Body" and actually be able to overwrite the body of the blog post. This is a potential disaster!
How can you prevent this? You have a couple choices here. First, you could use the [Bind] attribute, either on the Comment type or on the Comment action parameter, to indicate which properties are approved or disapproved for binding. Personally, I prefer the "white-list" approach so that only the named properties can be bound to, rather than the "black-list" approach (which excludes specific properties, and allows binding to everything else).
The other alternative is that the (Try)UpdateModel methods on Controller have overloads which accept white-/black-list parameter lists to tell the system which properties are eligible for binding.
There is a breaking change here from MVC 1.0 and the [Bind] attribute. Previously, we only validated the things we bound values to, so excluding a property with [Bind] also ensured that the validators for that property wouldn't run. In MVC 2 RTM, since we've changed to Model Validation, those validators will be run now, even though it's not possible to bind any values into the model. While the system still allows partial editing, you can no longer get partial validation like you could in 1.0 (or in the early MVC 2 previews).
Wrapping It All Up
I considered titling this blog post "[Required] Still Doesn't Do What You Think". :)
I hope it's still clear that, while the change from Input Validation to Model Validation might make some things more predictable, it still has not (and cannot) transform the validation system into a security feature. You still need to be careful to consider the implications of bad guys "under posting" and "over posting" to your forms, to ensure the safety and integrity of your data.
Please enable JavaScript if you would like to comment on this blog.
powered by
Member since 11/2004Glossary of Trade & Shipping Terms - A
- @ - At (referring to price)A. & C.P. - Anchors and chains proveda.a. - "Always afloat, after arrival"A.A.D. - Annual aggregate deductiblea.a.r. - Against all risksA.B. - Able-bodied seamanA.B.S. - American Bureau of Shipping is an American ship classification society.a.c. - AccountA.C.A.S. - "Advisory, Conciliation and Arbitration Service"A.C.I.I. - Associate of Chartered Insurance InstituteA.C.V. - Air cushion vehicle (hovercraft)A.F. - Advanced freighta.f.a.a. - as far as applicableA.G.W.I. - "Atlantic, Gulf, West Indies Limits"a.h. - After hatchA.H.F. - American hull form (insurance policy)A.I.M.U. - American Institute of Marine Underwriters A.I.R.M.I.C. - Association of Insurance and Risk Managers in Industry and Commerce "Fonds Africain de Developpement, FAD) is an affiliate of the African Development Bank (AfDB) which provides interest-free loans to African countries for projects which promote economic and social development and improve international trade among members o" - A.M.I. - Absolute maximum loss A.M.V.E.R. - Automated Mutual-Assistance Vessel Rescue A.O. Voy. - Any one voyageA.O.B. - Any one bottomA.O.E. - Any one eventA.O.L. - Any one loss a.o.loc. - Any one location - A.O.O. - Any one occurrence A.O.R. - Any one risk A.O.V. - Any one vessel A.P. - Additional premium A.P.L. - As per list A.R. - All risks A.S.E.A.N. - Association of South East Asian Nations A.T.L. - Actual total lossA/C - Account currentA/o - Account ofA/P - Additional premiumA/R - All risks.
Against all risksA/S - "After sight, Account sales, Alonside (chartering)"A/T - American terms (grain trade)A/v - "Average, ad valorem (according to value)"AADFI - Association of African Development Finance InstitutionsAAEI - American Association of Exporters and ImportersAAIB - Arab-African International BankAATP - Association of African Trade Promotion OrganizationsABC - American Business CenterABCA - Association des Banques Centrales AfricainesAbdnt. - AbandonmentABEDA - Arab Bank for Economic Development in AfricaABI - "American Business Initiative, Automated Broker Interface"Absorption - "Absorption is investment and consumption purchases by households,businesses, and governments, both domestic and imported. When absorption exceeds production, the excess is the country's current account deficit."Abt. - AboutABTA - Association of British Travel AgentsAbu Dhabi Fund for Arab Economic Development.
- "ADFAED promotes economic and social development in African, Arab, and Asian developing countries. The Fund, which was created in July 1971, began operations in September 1974; headquarters are in Abu Dhabi"ACAB - Association of Central African BanksACC - Arab Cooperation CouncilAcc. - Acceptance. AcceptedAccession - "Accession is the process by which a country becomes a member of an international agreement, such as the General Agreement on Tariffs and Trade (GATT) or the European Community. Accession to the GATT involves negotiations to determine the specific obligat"Accession - "This refers, in general, to the process of a country joining the GATT. During accession to the GATT, a country accords tariff and other concessions that are its 'price of admission' to the GATT. Although accession to the GATT binds a country to the Genera"ACCJ - American Chamber of Commerce in Japanaccomplished bill of lading - Original bill of lading surrendered to the carrying ship at the discharge port in exchange for the goods.ACCT - Agency for Cultural and Technical CooperationAcct - AccountACDA - Arms Control and Disarmament AgencyACEP - Advisory Committee on Export PolicyACH - Automated ClearinghouseACP - "African, Caribbean, and Pacific"ACP - "African, Caribbean and Pacific States"ACPC - Association of Coffee Producing CountriesACS - Automated Commercial SystemACTPN - Advisory Committee on Trade Policy and NegotiationsACU - Asian Clearing UnionAD - AntidumpingAd Val - Ad ValoremAd Valorem - "Literally:
according to value.
Any charge, tax, or duty that is applied as a percentage of value. "Ad Valorem Equivalent - "AVE is the rate of duty which would have been required on dutiable imports under that item, if the United States customs value of such imports were based on the United States port of entry value. "AD Valorem Tariff - "A tariff assessed as a percentage of the value of the goods cleared through customs. For example, 10 percent Ad Valorem means the tariff is 10 percent of the value of the goods."Ad. val. - Ad valorem-according to valueADB - Asian Development BankADB - Asian Development BankADF - "African Development Foundation, African Development Fund, Asian Development Fund"ADFAED - Abu Dhabi Fund for Arab Economic DevelopmentAdministrative Exception Notes - "CoCom controls exports at three levels, depending on the item and the proposed destination. At the lowest level, ""national discretion"" (also called ""administrative exception""), a member nation may approve the export on its own, but CoCom must be notified"Administrative Protective Order - "An Administrative Protective Order, APO, is used to protect proprietary data that is obtained during an administrative proceeding. Within Commerce, APO is most frequently used in connection with Antidumping and Countervailing Duty investigations to prohi"Administrative Review - "Each year, beginning on the anniversary of the date of publication of an antidumping duty order, the Commerce Department's International Trade Administration is required to review and determine the amount of any antidumping duty, if an interested party re"ADRs - American Depository ReceiptsADS - Agent Distributor Service ADS provides a custom search overseas for interested and qualified foreign representatives on behalf of a U.S. exporter. Officers abroad conduct the search and prepare a report identifying up to six foreign prospects that have examined the U.S. firm's product literature and have expressed interest in representing the U.S. firm's products.Advanced Technology Products - "About 500 of some 22,000 commodity classification codes used in reporting U.S. merchandise trade are identified as ""advanced technology"" codes and they meet the following criteria: -The code contains products whose technology is from a recognized high tec"Advisory Committee on Export Policy - "The Advisory Committee on Export Policy, ACEP, is an interagency dispute resolution body that operates at the Assistant Secretary level. ACEP is chaired by C membership includes the Departments of Defense, Energy, and State, the Arms Control and "Advisory Committee on Trade Negotiations (ACTN)
- "A group appointed by the U.S. President to advise him on matters of trade policy and related issues, including trade agreements."Advisory Committee on Trade Policy and Negotiations - "The ACTPN is a group (membership of 45; two-year terms) appointed by the President to provide advice on matters of trade policy and related issues, including trade agreements. The 1974 Trade Act requires the ACTPN's establishment and broad representation"Advocacy Center - "The Advocacy Center, established in November 1993, facilitates high-level U.S. official advocacy to assist U.S. firms competing for major projects and procurements worldwide. The Center is directed by the Trade Promotion Coordinating C offices ar"AECA - Arms Export Control ActAEF - Africa Enterprise FundAEN - Administrative Exception NoteAERP - Automated Export Reporting ProgramAfDB - African Development BankAfDF - African Development FundAFESD - Arab Fund for Economic and Social DevelopmentAffiliate - An affiliate is a business enterprise located in one country which is directly or indirectly owned or controlled by a person of another country to the extent of 10 percent or more of its voting securities for an incorporated business enterprise or an equiAffiliated Foreign Group - "An affiliated foreign group means (a) the foreign parent, (b) any foreign person, proceeding up the foreign parent's ownership chain, which owns more than 50 percent of the person below it up to and including that person which is not owned more than 50 pe""Affreightment, contract of " - "An agreement by a steamship line to provide cargo space on a vessel at a specified time for a specified price to accommodate an exporter or importer, who then becomes liable for payment even if he is later unable to make the shipment."AFREXIMBANKAfrican Export-Import Bank - Africa Enterprise Fund - "The AEF, operating under the International Finance Corporation, began operations in late 1989. The Fund assists small and medium-size enterprises in sub-Saharan Africa, supports investment projects, and promotes development of private enterprises in Afri"Africa Project Development Facility - The APDF seeks to accelerate development of productive enterprises sponsored by private African entrepreneurs as a means of generating self-sustained economic growth and productive employment in Sub-Saharan Africa. The facility provides advisory servicesAfrican Development Bank - AfDB (French: Banque Africaine de Developpement) provides financing through direct loans to African member states to cover the foreign exchange costs incurred in Bank-approved development projects in those countries. Fifty-one African countries are memberAfrican Development Foundation - "ADF provides economic assistance to groups and institutions involved in development projects at the local level. The foundation's assistance, designed as a complement to the U.S. foreign aid program, is awarded only to native African organizations and in"African Development Fund - The ADF (or AfDF) (French:African Export-Import Bank - "AFREXIMBANK offers short-term export trade financing to African exporters aimed at enhancing intra-African trade and Africa's exports. Agreement to create the bank was basedon a January 1993 agreement reached in Cairo, Egypt among African governments, ce"African Management Services Company - "AMSCO provides temporary managers and management training to support the development of African companies. AMSCO works through a network of representatives in A its clients include privately owned companies, public sector companies, and subsidiarie"African Regional Organization for Standardization - "ARSO (French: Organisation Regionale Africaine de Normalisation, ORAN) promotes and coordinates standardization, quality control, certification, and metrology practices in Africa. The Organization has been developing African Regional Standards (ARS) in "aft - At or towards
the rear of a ship.AFTA - ASEAN Free Trade AreaAfter Date - "A term used on a draft, bill of exchange or note indicating the date from which a draft will begin counting days until maturity. If an exporter draws a draft and stipulates a payment ""30 days after date"", the draft is due 30 days from the date on which it"AG - "Aktiengesellschaft, Australia Group"Agence de Cooperation Culterelle et Technique - "The ACCT (English: Agency for Cultural and Technical Cooperation) was created in 1970 to promote cultural and technical cooperation among French-speaking countries. Members include: Belgium, Benin, Burkina. Burundi, Canada, Central African Republic, Ch"Agency for International Development - "AID was created in 1961 to administer foreign economic assistance programs of the U.S. Government. AID has field missions and representatives in approximately 70 developing countries in Africa, Latin America, the Caribbean, and the Near East. "Agent/Distributor Service - "The Agent/Distributor Service, ADS, is an International Trade Administration (ITA) fee-based service which locates foreign import agents and distributors."Agrement - Agreement by one government to accept the accreditation of an ambassador from another government. AGRICOLA - Agricultural OnLine AccessAgricultural Marketing Service - "Among its activities, the Agriculture Deparment's AMS is available to foreign buyers to assure that any product shipped overseas meets contract specifications. The service is operated on a user-fee basis. AMS works with the buyers to write a specificati"Agricultural Officers - "Agricultural officers are embassy officials who are responsible for addressing agricultural trade policy issues and preparing reports on agricultural commodities such as rice, wheat, and dairy products. These officers promote U.S. exports by providing ma"AGRIS - Agriculture Information SystemAgt. - "Agent, Against, Agreement"AIB - Arab International BankAIBD - Association of International Bond DealersAID - Agency for International DevelopmentAID - Agency for International DevelopmentAide-Memoire - A short written summary of oral remarks made to a foreign government representative and left with that individual. AIES - Automated Information Exchange SystemAIG - Airbus Industries GroupAIMS - Agriculture Information and Marketing ServicesAir Cargo Agent - A type of freight forwarder who specializes in air cargo and acts for airlines that pay him a fee (usually 5%). The Air Cargo Agent is registered with the International Air Transport Association (IATA).Air Freight Forwarder - "A type of freight forwarder who specializes in air cargo. The Air Freight Forwarder usually consolidates the air shipments of various exporters, charging them for actual weight and deriving his profit by paying the airline the lower consolidated rate. He "Air Waybill - "An AWB is a bill of lading which covers both domestic and international flights transporting goods to a specified destination. Technically, it is a non-negotiable instrument of air transport which serves as a receipt for the shipper, indicating that the "Air Waybill (Of Lading) - "A signed receipt and a contract to deliver goods by air. Such bills are non-negotiable and do not convey title to the goods as do ""To Orders"" bills of lading used by ocean and land carriers. The title passes to the party to whom the goods are consigned (t"Airbus Industries Group - "AIG is a supernational management organization responsible for design, development, manufacture, marketing, sales and support of selected commercial aircraft. Member countries are France, Germany, Spain, and the United Kingdom. Airbus Industrie, G.I.E. "Aircraft Agreement (ATCA) - "Formally known as the ''Agreement on Trade in Civil Aircraft.'' (ATCA), this MTN agreement is the only major sector-specific civil aircraft agreement. It establishes a framework of rules governing the conduct of trade in civil aircraft based on commercial"AIST - Agency for Industrial Science TechnologyAIT - American Institute in TaiwanAIT - American Institute in TaiwanAKA - Ausfuhrkredit-GesellschaftAktiengesellschaft - "AG (German, meaning: ""stock company"") is a corporation with a separate legal personality which must have at least five partners. The firm name usually reflects the activities of the company and must include ""AG."" "ALADI - Asociacion Latinoamericana de IntegracionALIDE - "Association Latinoamericana de Institutiones Financieras, de Desarrollo"All Risks Coverage - "All Risks Coverage, a type of marine insurance, is the broadest kind of standard coverage, but excludes damage caused by war, strikes, and riots."All-Risk Clause - An insurance provision that all loss or damage to goods is insured except inherent vice (self-caused).Alongside - "A phrase referring to the side of a ship. Goods to be delivered ""alongside"" are to be placed on the dock or lighter within reach of the transport ship's tackle so that they can be loaded aboard the ship. Goods are delivered to the port of embarkation, b"AMB - AmbassadorAMCHAM - American Chamber of CommerceAmendments - Article XXX of the GATT Agreement provides that amendments (that become effective upon acceptance by two thirds of the Contracting Parties) are to be effective only for those parties which accept them.American Business Center - "The ABC program provides U.S. companies which are exploring or establishing commercial opportunities in the Newly Independent States of the former Soviet Union with business services such as telephone and fax, temporary office space, market information, a"American Business Initiative - "The ABI, or American Business and Private Sector Development Initiative for Eastern Europe, emphasizes the export of American telecommunciations, energy, environment, housing, and agriculture products and services to Eastern European countries. "American Depository Receipts - "ADRs are negotiable receipts for the securities of a foreign company which are kept in the vaults of an American bank, allowing Americans to trade the foreign securities in the United States while accruing any dividends and capital gains. "American Institute in Taiwan - "The AIT is a non-profit corporation that represents U.S. commerical, cultural, and other interests in Taiwan in lieu of an embassy. In 1979, the United States terminated formal diplomatic relations with Taiwan when it recognized the People's Republic of "American Traders Index - "The American Traders Index, ATI, is the U.S. and Foreign Commercial Service headquarters compilation of individual US&FCS domestic client files, for use by overseas posts to generate mailing lists. "AMF - Arab Monetary Fundamidships - At or towards the middle of a ship.AMS - "Agricultural Marketing Service, Automated Manifest System"AMSC - African Management Services Companyamt. - AmountAMU - Arab Maghreb UnionAndean Group - The Andean Group (Spanish: Grupo A sometimes referred to as Pacto Andino or Corporation Adino de F formal reference is Acuerdo de Cartegana in recognition of the Group's establishment in Cartegena in October 1969) is an association of Latin Andean Reserve Fund - "The Andean Reserve Fund (Spanish: Fondo Andina de Reservas), associated with the Andean Group, was established to strengthen the balance of payments positions of member countries by offering credit, guarantee loans, and promoting compatibility among memb"Andean Trade Preference Act - "The ATPA is a unilateral trade benefit program designed to promote economic development through private sector initiative in the four Andean countries of Bolivia, Colombia, Ecuador, and Peru. The ATPA encourages alternatives to coca cultivation and produ"ANF - Arrival notification formAnti-Dumping Clause - A tariff imposed to discourage sale of foreign goods in the United States market at very low prices (below foreign country's domestic market) which might hurt U.S. manufacturers.Antidumping - "Antidumping, as a reference to the system of laws to remedy dumping, is defined as a converse of dumping."Antidumping Duty - A duty assessed on imported merchandise which is subject to an antidumping duty order. The antidumping duty is assessed on an entry-by-entry basis in an amount equal to the difference between the United States price of that entry and the foreign market vAntidumping Duty Order - "A notice issued following final determination of sales at less than fair value and material injury, or threat of material injury, providing for the imposition of antidumping duties."Antidumping Investigation Notice - The notice published in the Federal Register announcing the initiation of an antidumping investigation. An investigation must be initiated within 20 days of the filing of a valid petition.Antidumping Petition - "A petition filed on behalf of an affected United States industry, alleging that foreign merchandise is being sold in the United States at ""less than fair value"" and that such sales are causing or threatening material injury to, or materially retarding the"Antidumping/Countervailing Duty System - "The Antidumping/Countervailing Duty System, a part of Customs' Automated Commercial System, contains a case reference database and a statistical reporting system to capture data for International Trade Commission reports on antidumping and countervailing "AOSIS - Alliance of Small Island StatesAP - Administrative Protective OrderAPAC - Auto Parts Advisory CommitteeAPDF - Africa Project Development FacilityAPEC - Asian-Pacific Economic CooperationAPI - American Petroleum InstituteAppd. - ApprovedArab Bank for Economic Development in Africa - The ABEDA (French: Banque Arabe pour le Developpement Economique en Afrique -- BADEA) was created by the League of Arab States in November 1973 (began operations in March 1975) to promote economic and technical cooperation between Arab and African statesArab Cooperation Council - "The ACC was created in 1989 to promote economic cooperation and integration. Members include Egypt, Iraq, Jordan, and North Yemen. The ACC, partly intended as a counterpart to Gulf Cooperation Council, was created one day subsequent to the establishment"Arab Fund for Economic and Social Development - "AFESD promotes regional economic integration and social development in Arab states. Members include: Algeria, Bahrain, Djibouti, Egypt, Iraq, Jordan, Kuwait, Lebanon, Libya, Mauritania, Morocco, Oman, Qatar, Saudi Arabia, Somalia, Sudan, Syria, Tunisia,"Arab International Bank - "The AIB provides financing to support development of foreign trade among member nations and other Arab states. The Bank was established in October 1971; headquarters are in Cairo, Egypt. Member include: the governments of Oman, Qatar, and United Arab E"Arab Maghreb Union - "The AMU (French: Union du Maghreb Arabe, UMA) encompasses Algeria, Libya, Mauritania, Morocco, and Tunisia. The Union was established in February 1989 to foster integration of the Maghreb economy. The Union also seeks to join the AMU and the Gulf Coope"Arab Monetary Fund - "The AMF, originally aimed at correcting chronic deficits in the balance of payments in most member states, promotes Arab integration in monetary and economic affairs. The Fund's priorities have included: (a) addressing payments imbalances, (b) creating "Arab Trade Financing Program - "The ATFP promotes trade among Arab countries and exports from Arab countries. The Program was established in 1989 by the Arab Monetary F headquarters are in Abu Dhabi, United Arab Emirates. "Arab-African International Bank ous buying and selling of the same commodity or foreign exchange in two or more markets in order to take advantage of price differentials. Arbitrage - The practice of exchanging the currency of one country for that of another or a series of countries to gain an advantage from the differences in exchange rates.Arbitration Clause - A clause in a sales contract outlining the method under which disputes will be settled.Arms Control and Disarmament Agency - ACDA is an independent agency within the State Department. ACDA participates in interagency working groups that discuss export license applications requiring dispute resolution. ACDA is interested in dual-use license applications from a non-proliferatioArr. T. L. - Arranged total lossArrangement on Guidelines for Officially Supported Export Credits - "The Arrangement is an international agreement under Organization for Economic Cooperation and Development auspices governing the conditions -- such as interest rate, repayment term, and cash downpayment -- of medium- and long-term of "arrest - Seizure of a ship by an authority of a court of law either as a debt security or to prevent the ship from departing until a dispute is settled.ARS - African Regional Organization for StandardizationAsDF - Asian Development FundASEAN - Association of Southeast Asian NationsASEAN - Association of South-East Asian NationsASEAN Free Trade Area - "The Association of Southeast Asian Nations (ASEAN) agreed in January 1992 to create a free trade area (ASEAN Free Trade Area, or AFTA) with use of a common effective preferential tariff. Under the agreement ASEAN members will cut tariff rates within 15 y"Asia Pacific Economic Cooperation - "APEC, established in November 1989, is an informal grouping of Asia Pacific countries that provides a forum for Ministerial level discussion of a broad range of economic issues. APEC includes the six ASEAN countries (Brunei, Indonesia, Malaysia, Philippi"Asian Clearing Union - "The ACU promotes regional trade and economic cooperation, including arrangements to conserve foreign exhcange and encourage domestic currencies in trade. Members include Bangladesh, India, Iran, Myanmar, Nepal, Pakistan, and Sri L Bhutan, Malaysia, "Asian Development Bank - "The ADB helps finance economic development in developing countries in the Asian and Pacific area through the provision of loans on near-market terms, with its Ordinary Capital Resources (OCR), and on concessional terms, through the Asian Development Fund "Asian Development Fund - "The ADF (or AsDF), an affiliate of the Asian Development Bank, lends funds on concessionary terms to the Bank's least developed member countries."Assessment - The imposition of antidumping duties on imported merchandise.Association of African Development Finance Institutions - "AADFI (French: Association des Institutions Africaines de Financement du Developpement, AIAFD) promotes cooperative financing for social development in Africa and economic integration. The Association was established in March 1975; headquarters are in A"Association of African Trade Promotion Organizations - "AATPO promotes inter-African trade, harmonization of commercial policies, communication among African states in trade matters, and research and training. The organization, which has about 26 members, was established in 1975 under the auspieces of the Org"Association of Central African Banks - "ACAB (French: Association des Banques Centrales Africanines, ABCA) promotes cooperation among monetary, banking, and financial institutions in Africa. Members include two African regional banks and about 32 national banks. The Association was created i"Association of International Bond Dealers - The AIBD provides a forum for over 500 members from 30 countries to review international securities market matters. The primary objectives of the Association are to provide a basis for examinaitn and discussion of questions relating to the secondary markAssociation of Southeast Asian Nations - "ASEAN was established in 1967 to promote political, economic, and social cooperation among its six member countries: Indonesia, Malaysia, Philippines, Singapore, Thailand, and Brunei. ASEAN headquarters are in Jakarta, Indonesia. In January 1992, ASEAN"At. wt. - Atomic WeightATFP - Arab Trade Financing Programathwartships - Across the ship or from side to side.athwartships - Across the ship or from side to side. ATI - "American Traders Index, Andean Trade Initiative"Atl. - AtlanticATLAS - Automated Trade Locator Assistance NetworkATMIC - Agricultural Trade and Marketing Information CenterATOs - Agricultural Trade OfficesATP - Advanced Technology ProductsATPA - Andean Trade Preference ActATPI - Andean Trade Preference InitiativeAUMA - "Die Ausstellungs- und Messe-Ausschuss der Deutschen, Wirtschaft"Ausfuhrkredit-Gesellschaft - AKA (English: Export Credit Establishment) is an association of German banks which provide medium and long-term funding for exports. Ausstellungs (Die) - und Messe-Ausschuss der Deutschen Wirtschaft - "AUMA (German: the German Industry Council for Exhibitions and Trade Fairs) promotes exports by bringing together government, semiprivate, and private organizations in the coordination of domestic and overseas trade events. AUMA is a private organization "Australia Group - "The Australia Group, AG, is an informal forum through which 22 industrialized nations cooperate to curb proliferation of chemical and biological weapons through a supply approach. The AG's first meeting, held at the Australian Embassy in Paris in June 19"Automated Broker Interface - "ABI, a part of Customs' Automated Commercial System, permits transmission of data pertaining to merchandise being imported into the United States. Qualified participants include brokers, importers, carriers, port authorities, and independent data process"Automated Clearinghouse - The Automated Clearinghouse (ACH) is a feature of the Automated Broker Interface which is a part of Customs' Automated Commercial System. The ACH combines elements of bank lock box arrangements with electronic funds transfer services to replace cash or cAutomated Commercial System - "The Customs Service's Automated Commercial System, ACS, is a joint public-private sector computerized data processing and telecommunications system linking customhouses, members of the import trade community, and other government agencies with the Customs"Automated Export Reporting Program - The AERP provides for electronic submission of most information required on the Shipper's Export Declaration. The program was initiated in 1969 with the intent of enabling large volume exporters to submit electronically and facilitate Census Bureau data Automated Information Exchange - "AIES, a part of Customs' Automated Commercial System, allows for exchange of classification and value information between field units and headquarters. "Automated Manifest Systems - "AMS, a part of Customs' Automated Commercial System (ACS) controls imported merchandise from the time a carrier's cargo manifest is electronically transmitted to Customs until control is relinquished to another segment of the ACS. "Automated Trade Locator Assistance Network - "ATLAS is a Small Business Administration-sponsored, contractor-operated, automated system which provides market research information and statistics on world markets by SIC code (and possibly harmonized system). Indirect access is available for businesses"AUTOVON - Automatic Voice NetworkAux. - Auxiliary VesselAv. - AverageAv. disbts. - Average disbursementsAVE - Ad Valorem EquivalentAWB - Airway Bill
Developed by Copyright (C) 2016 TradePort. All Rights Reserved.

我要回帖

更多关于 every students 的文章

 

随机推荐