[英]regex to escape non-html tags' angle brackets
I have an html based text (with html tags), I want to find words that occur within angle brackets and replace the brackets with < and > or even when angle brackets are used as math symobls 我有一个基于html的文本(带有html标签),我想查找出现在尖括号中的单词,并用<和>替换尖括号,甚至当尖括号用作数学符号时
eg: 例如:
String text= "Hello, <b> Whatever <br /> <table> <tr> <td width="300px">
1 < 2 This is a <test> </td> </tr> </table>";
I want this to be : 我希望这是:
Hello, <b> Whatever <br /> <table> <tr> <td width="300px">
1 < 2 This is a < test > </td> </tr> </table>
THANKS in advance 提前致谢
I would suggest you to use Html Cleaner 我建议您使用HTML Cleaner
If you look at the HomePage the example shows exactly how text is escaped. 如果查看HomePage,该示例将准确显示文本如何转义。
<td><a href=index.html>1 -> Home Page</a>
is converted in 转换成
<td>
<a href="index.html">1 -> Home Page</a>
</td>
it will normalize your html to conform to standard xHtml. 它将规范化您的html以符合标准xHtml。 I used it in the past and (IMHO) it's pretty solid and more reliable than jTidy&Co.
我过去曾用过它,但(IMHO)它比jTidy&Co更可靠且更可靠。 (and of course it's better then use regex or replace strategies...)
(当然最好使用正则表达式或替换策略...)
Please see RegEx match open tags except XHTML self-contained tags and don't use regex to parse html. 请参阅RegEx匹配打开的标签(XHTML自包含标签除外),并且不要使用regex解析html。 Use a SGML parser but don't use regex.
使用SGML解析器,但不要使用正则表达式。 It would fail to often.
它经常会失败。 HTML isn't a regular language.
HTML不是常规语言。
If it were not for CSS, Javascript, and CData sections, it would be possible. 如果不是CSS,Javascript和CData部分,则有可能。
If you are only dealing with a subset of HTML, you could make the assumption that angle brackets not surrounded by valid element identifier characters can be encoded. 如果仅处理HTML的子集,则可以假设可以对未用有效元素标识符字符包围的尖括号进行编码。
Something like "<(?=[^A-Za-z_:0-9/])" -> "<" and "(?<=[^A-Za-z_:0-9/])>" -> ">" 类似于“ <(?= [^ A-Za-z_:0-9 /])”->“ <”和“(?<= [^ A-Za-z_:0-9 /])>”- >“>”
But, unless you are generating the HTML yourself and KNOW that it has no embedded CSS, javascript, CData, or object sections... 但是,除非您自己生成HTML并知道它没有嵌入式CSS,javascript,CData或对象部分,否则...
As fraido said, don't use regular expressions for non-regular languages. 就像fraido所说的,不要对非规则语言使用正则表达式。
As everyone says, you shouldn't rely on Regular Expressions to parse HTML. 众所周知,您不应该依赖正则表达式来解析HTML。 They simply can't do it.
他们根本做不到。 But, in my case, I wanted to capture any angle brackets that didn't look like they were in an HTML tag, and escape them.
但是,就我而言,我想捕获看起来好像不在HTML标记中的任何尖括号,然后将其转义。 Since everything was going through a sanitizer afterwards security wasn't a concern, and the results just needed to be good enough to catch most situations, not all.
由于事后所有事情都要经过消毒器处理,因此安全性不是问题,而且结果只需要足够好就可以捕获大多数情况,而不是全部。
You need a Regexp Library that supports zero-width lookahead assertions. 您需要一个支持零宽度超前声明的Regexp库。 In my case, that was Oniguruma in Ruby 1.8.
就我而言,这就是Ruby 1.8中的Oniguruma。
To match the less than symbols (<), I did: 为了匹配小于符号(<),我做到了:
/<(?!(/?[A-Za-z_:0-9]+\s?/?>))/
Matching the greater than (>) symbols is harder. 匹配大于(>)符号比较困难。 Most libraries don't support zero-width lookbehind assertions of a variable length.
大多数库不支持可变长度的零宽度后置断言。 So you cheat: reverse the string, run a lookahead assertion, and reverse it back afterwards, using the following pattern:
因此,您作弊:反转字符串,运行先行断言,然后使用以下模式反转其后:
>(?!(/?\s?[A-Za-z_:0-9]+/?<))
So, my code looks a bit like: 因此,我的代码看起来像:
match_less_than = Oniguruma::ORegexp.new('<(?!(/?[A-Za-z_:0-9]+\s?/?>))')
match_less_than.gsub!(string, '<')
match_greater_than = Oniguruma::ORegexp.new('>(?!(/?\s?[A-Za-z_:0-9]+/?<))')
string = match_greater_than.gsub(string.reverse, '>'.reverse).reverse
Nasty, huh? 讨厌吧?
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.