更多相关文档HTML字符实体（Character Entities），转义字符串（Escape Sequence）
为什么要用转义字符串？
HTML中&，&，&等有特殊含义（&，&，用于链接签，&用于转义），不能直接使用。这些符号是不显示在我们最终看到的网页里的，那如果我们希望在网页中显示这些符号，该怎么办呢？
这就要说到HTML转义字符串（Escape Sequence）了。
（Escape Sequence）也称字符实体(Character Entity)。在HTML中，定义转义字符串的原因有两个：第一个原因是像“&”和“&gt”这类符号已经用来表示HTML标签，因此就不能直接当作文本中的符号来使用。为了在HTML文档中使用这些符号，就需要定义它的转义字符串。当解释程序遇到这类字符串时就把它解释为真实的字符。在输入转义字符串时，要严格遵守字母大小写的规则。第二个原因是，有些字符在ASCII字符集中没有定义，因此需要使用转义字符串来表示。
转义字符串的组成
转义字符串（Escape Sequence），即字符实体（Character Entity）分成三部分：第一部分是一个&符号，英文叫ampersand；第二部分是实体（Entity）名字或者是#加上实体（Entity）编号；第三部分是一个分号。
比如，要显示小于号（&），就可以写 & 或者 < 。
用实体（Entity）名字的好处是比较好理解，一看lt，大概就猜出是less than的意思，但是其劣势在于并不是所有的浏览器都支持最新的Entity名字。而实体(Entity)编号，各种浏览器都能处理。
提示：实体名称（Entity）是区分大小写的。
备注：同一个符号，可以用“实体名称”和“实体编号”两种方式引用，“实体名称”的优势在于便于记忆，但不能保证所有的浏览器都能顺利识别它，而“实体编号”则没有这种担忧，但它实在不方便记忆。
如何显示空格？
通常情况下，HTML会自动截去多余的空格。不管你加多少空格，都被看做一个空格。比如你在两个字之间加了10个空格，HTML会截去9个空格，只保留一个。为了在网页中增加空格，你可以使用&表示空格。
HTML特殊转义字符列表
最常用的字符实体Character Entities
半方大的空白
全方大的空白
不断行的空白格
已注册商标
商标（美国）
ISO 8859-1 (Latin-1)字符集
HTML 4.01 支持 ISO 8859-1 (Latin-1) 字符集。
备注：为了方便起见，以下表格中，“实体名称”简称为“名称”，“实体编号”简称为“编号”
数学和希腊字母标志symbols, mathematical symbols, and Greek letters
重要的国际标记markup-significant and internationalization characters
JavaScript转义符
横向跳格 (Ctrl-I)
编程的时候要注意特殊字符的问题，很多运行时出现的问题都是因为特殊字符的出现而引起的。
注意，由于反斜杠本身用作转义符，因此不能直接在脚本中键入一个反斜杠。如果要产生一个反斜杠，必须一起键入两个反斜杠 (\\)。
编码转换（to Unicode）
（程序代码来源于网络）
&&&& test = "你好abc"
&&&& str = ""
&&&& for( i=0;&&& i&test. i++ )
temp = test.charCodeAt(i).toString(16);
str&&& += "\\u"+ new Array(5-String(temp).length).join("0") +
&&&& document.write (str)
Function Unicode(str1)
&&&& Dim str,temp
&&&& str = ""
&&&& For i=1&&& to len(str1)
temp = Hex(AscW(Mid(str1,i,1)))
If len(temp) & 5 Then&&& temp = right("0000" & temp, 4)
str = str & "\u" & temp
&&&& Unicode = str
End Function
Function htmlentities(str)
&&&& For i = 1 to Len(str)
&&&&&&&& char = mid(str, i, 1)
&&&&&&&& If Ascw(char) & 128 then
&&&&&&&&&&&& htmlentities = htmlentities & "&#" & Ascw(char) & ";"
&&&&&&&& Else
&&&&&&&&&&&& htmlentities = htmlentities & char
&&&&&&&& End if
End Function
coldfusion版
function nochaoscode(str)
&&&& var new_str = “”;
&&&& for(i=1; i lte len(str);i=i+1){
&&&&&&&& if(asc(mid(str,i,1)) lt 128){
&&&&&&&&&&&& new_str = new_str & mid(str,i,1);
&&&&&&&& }else{
&&&&&&&&&&&& new_str = new_str & “&##” & asc(mid(str,i,1));
&&&&&&&& }
&&&& return new_
在php中我们可以用mbstring的mb_convert_encoding函数实现这个正向及反向的转化。 如：
mb_convert_encoding ("你好", "HTML-ENTITIES", "gb2312"); //输出：你好
mb_convert_encoding ("你好", "gb2312", "HTML-ENTITIES"); //输出：你好
如果需要对整个页面转化，则只需要在php文件的头部加上这三行代码：
mb_internal_encoding("gb2312"); // 这里的gb2312是你网站原来的编码
mb_http_output("HTML-ENTITIES");
ob_start('mb_output_handler');
来源：HTML转义字符：
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CResistance Tolerance&&&& + / - 1 %B Value&&&&&&&&&&&& 3950K at 25/50 deg. CB Value Tolerance&&&&&&&& + / - 1 %&Temp.(deg. C)Rmax(k Ohms)Rnor(k Ohms)Rmin(k Ohms)-30-29-28-27-26-25-24-23-22-21-20975.8038944.2871-19950.6732920.5962891.3817-18896.7294868.8615841.7754-17846.1864820.3603795.2428-16798.8093774.8710751.5750-15754.3810732.1889710.5786-14712.7005692.1238672.0741-13673.5814654.4999635.8954-12636.8513619.1540601.8883-11602.3502585.9346569.9095-10569.9298554.7016539.8262-9539.4526525.3245511.5153-8510.7906497.6821484.8615-7483.8254471.6621459.7586-6458.4467447.1599436.1073-5434.5519424.0781413.8153-4412.0460402.3264392.7968-3390.8401381.8204372.9716-2370.8519362.4818354.2653-1352.0045344.2375336.60830334.2264327.0195319.93601317.4508310.7640304.18772301.6157295.4121289.30723286.6631280.9084275.24184272.5389267.2014261.94235259.1926254.2428249.36266246.5770241.9877237.46017234.6482230.3940226.19438223.3650219.4224215.52789212.6890209.0361205.425510202.5840199.2007195.854411193.0167189.8841186.783612183.9552181.0559178.184413175.3704172.6881170.029814167.2345164.7540162.294215159.5216157.2290154.953916152.2075150.0898147.986717145.2694143.3144141.371618138.6861136.8825135.088919132.4375130.7749129.120220126.5049124.9734123.448221120.8705119.4612118.056422115.5180114.2223112.929823110.4316109.2417108.053724105.5969104.5053103.414725101.0000100.000099.00002696.712795.713294.71462792.630691.633390.63782888.742687.749286.75832985.038684.050583.06553081.509080.527479.54973178.144677.170776.20123274.937073.971773.01153371.877970.922269.97213468.959868.014467.07523566.175565.241164.31343663.518262.595461.67983760.981460.070759.16773858.559157.661056.77103956.245655.360454.48374054.035553.163552.30044151.923551.065150.21584249.904949.060248.22504347.975247.144346.32324446.129845.313044.50624544.364943.562142.76964642.676441.887841.10964741.060740.286239.52244839.514338.753938.00444938.033937.287636.55245036.616335.884235.16315135.258734.540533.83355233.958233.253832.56085332.712132.021431.34235431.517830.840830.17545530.373129.709629.05765629.275528.625327.98685728.223027.586026.96075827.213526.589525.97725926.245025.633825.03436025.315624.717124.13036124.423723.837623.26336223.567522.993722.43156322.745422.183621.63366421.956021.406120.86786521.197720.659420.13286620.469219.942419.42726719.769319.253718.74976819.096618.592018.09906918.449917.956217.47407017.828217.345216.87357117.230416.757816.29657216.655416.193015.74197316.102315.649915.20877415.570215.127614.69617515.058114.625114.20327614.565214.141713.72917714.090713.676413.27297813.633913.228612.83417913.194012.797612.41188012.770312.382512.00538112.362211.982811.61398211.968911.597811.23728311.590011.227010.87438411.224710.869710.52488510.872710.525410.18818610.533210.19359.86378710.20599.87369.5511889.89029.56529.2499899.58589.26788.9594909.29208.98098.6794919.00858.70428.4094928.73508.43738.1489938.47108.17977.8977948.21617.93127.6554957.97007.69127.4215967.73247.45967.1958977.50297.23606.9780987.28127.02016.7677997.06706.81156.56471006.86016.61016.36861016.66016.41556.17931026.46686.22745.99641036.27996.04575.81971046.09935.87015.64891055.92465.70035.48391065.75575.53625.32451075.59235.37755.17031085.43435.22405.02131095.28145.07554.87721105.13344.93194.73791114.99034.79304.60311124.85174.65864.47271134.71754.52854.34661144.58774.40264.22451154.46194.28074.10641164.34014.16273.99211174.22224.04843.88151184.10793.93783.77431193.99723.83063.67061203.89003.72683.57021213.78613.62633.47291223.68543.52893.37871233.58773.43453.28741243.49313.34303.19901253.40143.25433.11331263.31243.16833.03021273.22613.08502.94971283.14243.00422.87171293.06132.92582.79601302.98252.84982.72271312.90612.77612.65151322.83202.70452.58261332.76012.63522.51571342.69022.56782.45071352.62252.50252.38781362.55672.43912.32671372.49282.37752.26741382.43082.31782.20981392.37052.25982.15401402.31202.20342.09971412.25522.14872.04711422.20002.09561.99601432.14632.04401.94631442.09421.99391.89811452.04361.94521.85131461.99431.89781.80581471.94651.85181.76161481.90001.80711.71871491.85471.76371.67701501.81081.72151.63641511.76801.68041.59701521.72641.64051.55871531.68601.60171.52151541.64671.56401.48531551.60841.52731.45011561.57121.49151.41581571.53491.45681.38251581.49971.42301.35011591.46541.39011.31861601.43201.35821.28801611.39951.32701.25821621.36781.29671.22921631.33701.26721.20091641.30701.23851.17341651.27781.21061.14671661.24941.18331.12071671.22171.15681.09531681.19471.13101.07061691.16841.10591.04661701.14281.08141.02321711.11791.05761.00041721.09351.03430.97821731.06981.01170.95661741.04670.98960.93551751.02420.96810.91501761.00230.94720.89501770.98090.92680.87561780.96010.90690.85661790.93970.88750.83811800.91990.86860.82001810.90060.85010.80241820.88170.83210.78531830.86330.81460.76861840.84540.79750.75231850.82790.78080.73641860.81080.76460.72091870.79410.74870.70581880.77790.73320.69111890.76200.71810.67671900.74650.70340.66271910.73140.68900.64901920.71660.67490.63561930.70220.66120.62261940.68820.64790.60991950.67440.63480.59751960.66100.62210.58531970.64790.60960.57351980.63510.59750.56201990.62270.58560.55072000.61050.57400.53972010.59850.56270.52902020.58690.55170.51852030.57550.54090.50822040.56440.53030.49822050.55360.52000.48842060.54300.50990.47892070.53260.50010.46962080.52250.49050.46042090.51260.48110.45152100.50290.47190.44282110.49340.46300.43432120.48420.45420.42602130.47510.44560.41792140.46630.43720.41002150.45760.42900.40222160.44920.42100.39462170.44090.41320.38722180.43280.40550.38002190.42490.39800.37292200.41710.39070.36602210.40960.38360.35922220.40210.37650.35252230.39490.36970.34612240.38780.36300.33972250.38090.35640.33352260.37410.35000.32742270.36740.34370.32152280.36090.33760.31572290.35450.33150.31002300.34830.32570.30452310.34220.31990.29902320.33620.31420.29372330.33040.30870.28852340.32460.30330.28342350.31900.29800.27842360.31350.29280.27352370.30810.28780.26872380.30290.28280.26402390.29770.27790.25942400.29270.27320.25492410.28770.26850.25052420.28290.26390.24622430.27810.25940.24202440.27340.25500.23792450.26890.25070.23382460.26440.24650.22982470.26000.24240.22592480.25570.23840.22212490.25150.23440.21842500.24740.23050.21482510.24330.22670.21122520.23940.22300.20772530.23550.21930.20422540.23170.21570.20092550.22790.21220.19762560.22430.20880.19432570.22070.20540.19112580.21720.20210.18802590.21370.19880.18502600.21030.19570.18202610.20700.19250.17912620.20370.18950.17622630.20050.18650.17342640.19740.18350.17062650.19430.18060.16792660.19130.17780.16522670.18840.17500.16262680.18550.17230.16012690.18260.16960.15752700.17980.16700.15512710.17710.16440.15272720.17440.16190.15032730.17170.15940.14802740.16910.15700.14572750.16660.15460.14352760.16410.15220.14132770.16160.14990.13912780.15920.14770.13702790.15680.14550.13492800.15450.14330.13292810.15220.14120.13092820.15000.13910.12892830.14780.13700.12702840.14560.13500.12512850.14350.13300.12322860.14140.13100.12142870.13940.12910.11962880.13740.12720.11792890.13540.12540.11612900.13350.12360.11442910.13160.12180.11282920.12970.12010.11112930.12790.11830.10952940.12600.11660.10792950.12430.11500.10642960.12250.11340.10492970.12080.11180.10342980.11910.11020.10192990.11750.10860.10053000.11580.10710.09903010.11420.10560.09763020.11270.10420.09633030.11110.10270.09493040.10960.10130.09363050.10810.09990.09233060.10670.09850.09103070.10520.09720.08983080.10380.09590.08853090.10240.09460.08733100.10100.09330.08613110.09970.09200.08503120.09830.09080.08383130.09700.08960.08273140.09580.08840.08163150.09450.08720.08053160.09330.08600.07943170.09200.08490.07833180.09080.08380.07733190.08970.08270.07633200.08850.08160.07523210.08740.08050.07433220.08620.07950.07333230.08510.07850.07233240.08400.07750.07143250.08300.07650.07043260.08190.07550.06953270.08090.07450.06863280.07990.07360.06783290.07880.07260.06693300.07790.07170.06603310.07690.07080.06523320.07590.06990.06443330.07500.06900.06353340.07410.06820.06273350.07310.06730.06203360.07220.06650.06123370.07140.06570.06043380.07050.06490.05973390.06960.06410.05893400.06880.06330.05823410.06800.06250.05753420.06710.06170.05683430.06630.06100.05613440.06550.06030.05543450.06480.05950.05473460.06400.05880.05413470.06320.05810.05343480.06250.05740.05283490.06180.05670.05213500.06100.05610.0515&&南京华巨电子有限公司是专注于NTC热敏电阻/PTC热敏电阻、NTC温度传感器、热电偶温度传感器、数字温度传感器的研发、生产和销售一站式服务的高新技术企业。产品的可靠性高、一致性好、性能价格比高、具有很强的市场竞争力,极受用户的好评和信赖, 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