我如何编码和解码HTML实体使用JavaScript或JQuery?
var varTitle = "Chris' corner";
我希望它是:
var varTitle = "Chris' corner";
你可以尝试这样做:
var Title = $('<textarea />').html("Chris'角”)。text (); console.log(标题); < script src = " https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js " > < /脚本>
J.S.小提琴。
更具互动性的版本:
$('form').submit(function() { var theString = $('#string').val(); var varTitle = $('<textarea />').html(theString).text(); $('#output').text(varTitle); return false; }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <form action="#" method="post"> <fieldset> <label for="string">Enter a html-encoded string to decode</label> <input type="text" name="string" id="string" /> </fieldset> <fieldset> <input type="submit" value="decode" /> </fieldset> </form> <div id="output"></div>
J.S.小提琴。
向页面中注入不受信任的HTML是危险的，如如何使用jQuery解码HTML实体中所述。
一种替代方法是使用PHP html_entity_decode的纯javascript实现(来自http://phpjs.org/functions/html_entity_decode:424)。这个例子应该是这样的:
var varTitle = html_entity_decode("Chris' corner");
我不建议使用jQuery代码作为答案。虽然它不会将要解码的字符串插入到页面中，但它确实会创建脚本和HTML元素等内容。这代码比我们需要的多。相反，我建议使用更安全、更优化的函数。
var decodeEntities = (function() {
// this prevents any overhead from creating the object each time
var element = document.createElement('div');
function decodeHTMLEntities (str) {
if(str && typeof str === 'string') {
// strip script/html tags
str = str.replace(/<script[^>]*>([\S\s]*?)<\/script>/gmi, '');
str = str.replace(/<\/?\w(?:[^"'>]|"[^"]*"|'[^']*')*>/gmi, '');
element.innerHTML = str;
str = element.textContent;
element.textContent = '';
}
return str;
}
return decodeHTMLEntities;
})();
http://jsfiddle.net/LYteC/4/
要使用这个函数，只需调用decodeEntities(“&”)，它将使用与jQuery版本相同的底层技术——但是没有jQuery的开销，并且在清除输入中的HTML标记之后。请参阅Mike Samuel关于如何过滤HTML标记的公认答案的评论。
这个函数可以很容易地作为jQuery插件使用，只需在您的项目中添加以下行即可。
jQuery.decodeEntities = decodeEntities;
我知道我有点晚了，但我认为我可以提供以下片段作为我如何使用jQuery解码HTML实体的示例:
var varTitleE = "Chris' corner";
var varTitleD = $("<div/>").html(varTitleE).text();
console.log(varTitleE + " vs. " + varTitleD);
不要忘记启动检查器/firebug以查看控制台结果——或者简单地将console.log(…)替换为/alert(…)
也就是说，以下是我的控制台通过谷歌Chrome检查器读取的内容:
Chris' corner vs. Chris' corner
就像Robert K说的，不要使用jQuery.html().text()来解码html实体，因为这是不安全的，因为用户输入永远不能访问DOM。阅读关于XSS的文章，了解为什么这是不安全的。
相反，尝试使用带有escape和unescape方法的Underscore.js实用带库:
_.escape（string）
转义插入HTML的字符串，替换&，<，>，"，'，和'字符。
_.escape('Curly, Larry & Moe');
=> "Curly, Larry & Moe"
_.unescape（string）
escape的反义词，代替&， <， >， "， `和& # x27;和他们没有逃脱的同伴。
_.unescape('Curly, Larry & Moe');
=> "Curly, Larry & Moe"
要支持解码更多字符，只需复制下划线unescape方法并向映射添加更多字符。
受Robert K的解决方案的启发，这个版本不剥离HTML标记，而且同样安全。
var decode_entities = (function() {
// Remove HTML Entities
var element = document.createElement('div');
function decode_HTML_entities (str) {
if(str && typeof str === 'string') {
// Escape HTML before decoding for HTML Entities
str = escape(str).replace(/%26/g,'&').replace(/%23/g,'#').replace(/%3B/g,';');
element.innerHTML = str;
if(element.innerText){
str = element.innerText;
element.innerText = '';
}else{
// Firefox support
str = element.textContent;
element.textContent = '';
}
}
return unescape(str);
}
return decode_HTML_entities;
})();
这里有一个不需要创建div的快速方法，并解码“最常见的”HTML转义字符:
function decodeHTMLEntities(text) {
var entities = [
['amp', '&'],
['apos', '\''],
['#x27', '\''],
['#x2F', '/'],
['#39', '\''],
['#47', '/'],
['lt', '<'],
['gt', '>'],
['nbsp', ' '],
['quot', '"']
];
for (var i = 0, max = entities.length; i < max; ++i)
text = text.replace(new RegExp('&'+entities[i][0]+';', 'g'), entities[i][1]);
return text;
}
要做到这一点，在纯javascript没有jquery或预定义一切，你可以循环编码的html字符串通过元素innerHTML和innerText(/textContent)属性的每解码步骤，这是必需的:
<html>
<head>
<title>For every decode step, cycle through innerHTML and innerText </title>
<script>
function decode(str) {
var d = document.createElement("div");
d.innerHTML = str;
return typeof d.innerText !== 'undefined' ? d.innerText : d.textContent;
}
</script>
</head>
<body>
<script>
var encodedString = "<p>name</p><p><span style=\"font-size:xx-small;\">ajde</span></p><p><em>da</em></p>";
</script>
<input type=button onclick="document.body.innerHTML=decode(encodedString)"/>
</body>
</html>
受Robert K的解决方案的启发，剥离html标签，防止执行脚本和事件处理程序，如:<img src=fake onerror="prompt(1)" > 在最新的Chrome, FF, IE上测试(应该可以在IE9上工作，但还没有测试)。
var decodeEntities = (function () {
//create a new html document (doesn't execute script tags in child elements)
var doc = document.implementation.createHTMLDocument("");
var element = doc.createElement('div');
function getText(str) {
element.innerHTML = str;
str = element.textContent;
element.textContent = '';
return str;
}
function decodeHTMLEntities(str) {
if (str && typeof str === 'string') {
var x = getText(str);
while (str !== x) {
str = x;
x = getText(x);
}
return x;
}
}
return decodeHTMLEntities;
})();
简单地调用:
decodeEntities('<img src=fake onerror="prompt(1)">');
decodeEntities("<script>alert('aaa!')</script>");
jQuery提供了一种编码和解码html实体的方法。
如果你使用"<div/>"标签，它会删除所有的html。
function htmlDecode(value) {
return $("<div/>").html(value).text();
}
function htmlEncode(value) {
return $('<div/>').text(value).html();
}
如果你使用"<textarea/>"标签，它将保留html标签。
function htmlDecode(value) {
return $("<textarea/>").html(value).text();
}
function htmlEncode(value) {
return $('<textarea/>').text(value).html();
}
为了在列表中添加另一个“受Robert K的启发”，这里是另一个不剥离HTML标签的安全版本。它不是通过HTML解析器运行整个字符串，而是只提取实体并转换它们。
var decodeEntities = (function() {
// this prevents any overhead from creating the object each time
var element = document.createElement('div');
// regular expression matching HTML entities
var entity = /&(?:#x[a-f0-9]+|#[0-9]+|[a-z0-9]+);?/ig;
return function decodeHTMLEntities(str) {
// find and replace all the html entities
str = str.replace(entity, function(m) {
element.innerHTML = m;
return element.textContent;
});
// reset the value
element.textContent = '';
return str;
}
})();
因为@Robert K和@mattcasey都有很好的代码，我想在这里贡献一个CoffeeScript版本，以防将来有人会使用它:
String::unescape = (strict = false) ->
###
# Take escaped text, and return the unescaped version
#
# @param string str | String to be used
# @param bool strict | Stict mode will remove all HTML
#
# Test it here:
# https://jsfiddle.net/tigerhawkvok/t9pn1dn5/
#
# Code: https://gist.github.com/tigerhawkvok/285b8631ed6ebef4446d
###
# Create a dummy element
element = document.createElement("div")
decodeHTMLEntities = (str) ->
if str? and typeof str is "string"
unless strict is true
# escape HTML tags
str = escape(str).replace(/%26/g,'&').replace(/%23/g,'#').replace(/%3B/g,';')
else
str = str.replace(/<script[^>]*>([\S\s]*?)<\/script>/gmi, '')
str = str.replace(/<\/?\w(?:[^"'>]|"[^"]*"|'[^']*')*>/gmi, '')
element.innerHTML = str
if element.innerText
# Do we support innerText?
str = element.innerText
element.innerText = ""
else
# Firefox
str = element.textContent
element.textContent = ""
unescape(str)
# Remove encoded or double-encoded tags
fixHtmlEncodings = (string) ->
string = string.replace(/\&#/mg, '&#') # The rest, for double-encodings
string = string.replace(/\"/mg, '"')
string = string.replace(/\"e;/mg, '"')
string = string.replace(/\_/mg, '_')
string = string.replace(/\'/mg, "'")
string = string.replace(/\"/mg, '"')
string = string.replace(/\>/mg, '>')
string = string.replace(/\</mg, '<')
string
# Run it
tmp = fixHtmlEncodings(this)
decodeHTMLEntities(tmp)
请参阅https://jsfiddle.net/tigerhawkvok/t9pn1dn5/7/或https://gist.github.com/tigerhawkvok/285b8631ed6ebef4446d(包括编译过的JS，可能比这个答案更新了)
以下是完整版本
function htmldecode(s){
window.HTML_ESC_MAP = {
"nbsp":" ","iexcl":"¡","cent":"¢","pound":"£","curren":"¤","yen":"¥","brvbar":"¦","sect":"§","uml":"¨","copy":"©","ordf":"ª","laquo":"«","not":"¬","reg":"®","macr":"¯","deg":"°","plusmn":"±","sup2":"²","sup3":"³","acute":"´","micro":"µ","para":"¶","middot":"·","cedil":"¸","sup1":"¹","ordm":"º","raquo":"»","frac14":"¼","frac12":"½","frac34":"¾","iquest":"¿","Agrave":"À","Aacute":"Á","Acirc":"Â","Atilde":"Ã","Auml":"Ä","Aring":"Å","AElig":"Æ","Ccedil":"Ç","Egrave":"È","Eacute":"É","Ecirc":"Ê","Euml":"Ë","Igrave":"Ì","Iacute":"Í","Icirc":"Î","Iuml":"Ï","ETH":"Ð","Ntilde":"Ñ","Ograve":"Ò","Oacute":"Ó","Ocirc":"Ô","Otilde":"Õ","Ouml":"Ö","times":"×","Oslash":"Ø","Ugrave":"Ù","Uacute":"Ú","Ucirc":"Û","Uuml":"Ü","Yacute":"Ý","THORN":"Þ","szlig":"ß","agrave":"à","aacute":"á","acirc":"â","atilde":"ã","auml":"ä","aring":"å","aelig":"æ","ccedil":"ç","egrave":"è","eacute":"é","ecirc":"ê","euml":"ë","igrave":"ì","iacute":"í","icirc":"î","iuml":"ï","eth":"ð","ntilde":"ñ","ograve":"ò","oacute":"ó","ocirc":"ô","otilde":"õ","ouml":"ö","divide":"÷","oslash":"ø","ugrave":"ù","uacute":"ú","ucirc":"û","uuml":"ü","yacute":"ý","thorn":"þ","yuml":"ÿ","fnof":"ƒ","Alpha":"Α","Beta":"Β","Gamma":"Γ","Delta":"Δ","Epsilon":"Ε","Zeta":"Ζ","Eta":"Η","Theta":"Θ","Iota":"Ι","Kappa":"Κ","Lambda":"Λ","Mu":"Μ","Nu":"Ν","Xi":"Ξ","Omicron":"Ο","Pi":"Π","Rho":"Ρ","Sigma":"Σ","Tau":"Τ","Upsilon":"Υ","Phi":"Φ","Chi":"Χ","Psi":"Ψ","Omega":"Ω","alpha":"α","beta":"β","gamma":"γ","delta":"δ","epsilon":"ε","zeta":"ζ","eta":"η","theta":"θ","iota":"ι","kappa":"κ","lambda":"λ","mu":"μ","nu":"ν","xi":"ξ","omicron":"ο","pi":"π","rho":"ρ","sigmaf":"ς","sigma":"σ","tau":"τ","upsilon":"υ","phi":"φ","chi":"χ","psi":"ψ","omega":"ω","thetasym":"ϑ","upsih":"ϒ","piv":"ϖ","bull":"•","hellip":"…","prime":"′","Prime":"″","oline":"‾","frasl":"⁄","weierp":"℘","image":"ℑ","real":"ℜ","trade":"™","alefsym":"ℵ","larr":"←","uarr":"↑","rarr":"→","darr":"↓","harr":"↔","crarr":"↵","lArr":"⇐","uArr":"⇑","rArr":"⇒","dArr":"⇓","hArr":"⇔","forall":"∀","part":"∂","exist":"∃","empty":"∅","nabla":"∇","isin":"∈","notin":"∉","ni":"∋","prod":"∏","sum":"∑","minus":"−","lowast":"∗","radic":"√","prop":"∝","infin":"∞","ang":"∠","and":"∧","or":"∨","cap":"∩","cup":"∪","int":"∫","there4":"∴","sim":"∼","cong":"≅","asymp":"≈","ne":"≠","equiv":"≡","le":"≤","ge":"≥","sub":"⊂","sup":"⊃","nsub":"⊄","sube":"⊆","supe":"⊇","oplus":"⊕","otimes":"⊗","perp":"⊥","sdot":"⋅","lceil":"⌈","rceil":"⌉","lfloor":"⌊","rfloor":"⌋","lang":"〈","rang":"〉","loz":"◊","spades":"♠","clubs":"♣","hearts":"♥","diams":"♦","\"":"quot","amp":"&","lt":"<","gt":">","OElig":"Œ","oelig":"œ","Scaron":"Š","scaron":"š","Yuml":"Ÿ","circ":"ˆ","tilde":"˜","ndash":"–","mdash":"—","lsquo":"‘","rsquo":"’","sbquo":"‚","ldquo":"“","rdquo":"”","bdquo":"„","dagger":"†","Dagger":"‡","permil":"‰","lsaquo":"‹","rsaquo":"›","euro":"€"};
if(!window.HTML_ESC_MAP_EXP)
window.HTML_ESC_MAP_EXP = new RegExp("&("+Object.keys(HTML_ESC_MAP).join("|")+");","g");
return s?s.replace(window.HTML_ESC_MAP_EXP,function(x){
return HTML_ESC_MAP[x.substring(1,x.length-1)]||x;
}):s;
}
使用
htmldecode("∑ >€");
@William Lahti的回答有一个更实用的方法:
var entities = {
'amp': '&',
'apos': '\'',
'#x27': '\'',
'#x2F': '/',
'#39': '\'',
'#47': '/',
'lt': '<',
'gt': '>',
'nbsp': ' ',
'quot': '"'
}
function decodeHTMLEntities (text) {
return text.replace(/&([^;]+);/gm, function (match, entity) {
return entities[entity] || match
})
}
原作者的答案在这里。
这是我最喜欢的解码HTML字符的方法。使用此代码的优点是还保留了标记。
function decodeHtml(html) {
var txt = document.createElement("textarea");
txt.innerHTML = html;
return txt.value;
}
例如:http://jsfiddle.net/k65s3/
输入:
Entity: Bad attempt at XSS:<script>alert('new\nline?')</script><br>
输出:
Entity: Bad attempt at XSS:<script>alert('new\nline?')</script><br>
这是另一个版本:
函数convertHTMLEntity(文本){ const span = document.createElement('span'); 返回文本 .replace (/ & [# A-Za-z0-9] +, / gi(实体、位置、文本)= > { 跨度。innerHTML =实体; 返回span.innerText; })； ｝ console.log (convertHTMLEntity(“大& lt;& # 163;500 '));
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