正则表达式 - 删除HTML注释跨越多个换行符 [英] Regular Expression - Remove HTML comment spanning multiple line breaks
问题描述
我使用这个脚本：
的 http://www.codeproject.com/Articles/11902/Convert-HTML-to-Plain-Text
要某些Outlook HTML转换为纯文本。
To convert some outlook HTML to plain text.
据近的作品，它留下的唯一的事情是CSS这在HTML注释标记前景的地方<！ - - > 除了<风格> 标签（被删除）
It nearly works, the only thing that it leaves behind is the CSS which outlook places in html comment tags <!-- --> in addition to <style> tags (which are removed)
这是原文：
<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 14 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-GB" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal">tesst<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:EN-GB">JOE BLOGS</span></b><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:dimgray;mso-fareast-language:EN-GB">
</div>
</body>
</html>
这是生成的文本：（注意HTML注释一直没有删除）
This is the resulting text: (note the HTML comment has not been removed)
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
-->
tesst
JOE BLOGS
我试图调整与附加取代StripHTML（）函数 - 但是这些没有任何工作。
I have tried adapting the StripHTML() function with the additional replaces - but these did not work either.
result = System.Text.RegularExpressions.Regex.Replace(result, "(<!--).*?(-->)", String.Empty, System.Text.RegularExpressions.RegexOptions.IgnoreCase)
result = System.Text.RegularExpressions.Regex.Replace(result, "<!--*-->", String.Empty, System.Text.RegularExpressions.RegexOptions.IgnoreCase)
请帮忙 - 这是我一直以来的午餐停留在2分钟的工作的 facedesk 的
Please help - this was a 2 minute job that i've been stuck on since lunch facedesk
干杯
修改1 ：也试过以下 - 仍然没有喜悦
Edit 1: also tried the following - still no joy
result = System.Text.RegularExpressions.Regex.Replace(result, "<!--.*-->", String.Empty, System.Text.RegularExpressions.RegexOptions.IgnoreCase)
result = System.Text.RegularExpressions.Regex.Replace(result, "<!--.*?-->", String.Empty, System.Text.RegularExpressions.RegexOptions.IgnoreCase)
编辑2：我注意到这个问题是越来越很多意见，任何人读这一定要三思而后行采取正则表达式的方法，而不是我推荐使用天猫（基于开放源代码的文本浏览器）的HTML转换为纯文本，我问过类似的问题的here 以及我公司提供基于应该让你的答案在编辑示例代码开始使用lynx.exe从.NET应用程序中。这是我们最后使用，并没有因为任何问题的方法。
Edit 2: I noticed this question was getting a lot of views, anyone reading this should definitely think twice about taking the regExp approach, instead i recommend using Lynx (OpenSource text based browser) to convert HTML to plain text, i asked a similar question here and i provide sample code in the edits based on the answers that should get you started using lynx.exe from within a .net application. This is the method we ended up using and haven't had any problems since.
推荐答案
有三个原因你的第二个正则表达式：
Your second regular expression for three reasons:
- 您需要使用
。来匹配任何字符。 - 的
*是贪婪的。你想*？懒洋洋地匹配。 - 您需要
RegexOptions.Singleline
- You need to use
.to match any character. - The
*is greedy. You want*?to match lazily. - You need
RegexOptions.Singleline.
试试这个：
result = Regex.Replace(result, "<!--.*?-->", "", RegexOptions.Singleline);
我强烈建议您不要使用正则表达式解析HTML。你会救自己痛苦的整个世界，如果你改用 HTML敏捷性包。
这篇关于正则表达式 - 删除HTML注释跨越多个换行符的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
