HTML文本到纯文本

HTML文本到纯文本

本文介绍了HTML文本到纯文本的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

Hai All,



如何使用C#将HTML文本转换为纯文本



请帮助我...



谢谢进展

Aatif Ali

Hai All,

How to Convert HTML text to Plain Text using C#

Please Help me ...

Thanks Advnce
Aatif Ali

推荐答案

private string StripHTML(string source)
{
    try
    {
        string result;

        // Remove HTML Development formatting
        // Replace line breaks with space
        // because browsers inserts space
        result = source.Replace("\r", " ");
        // Replace line breaks with space
        // because browsers inserts space
        result = result.Replace("\n", " ");
        // Remove step-formatting
        result = result.Replace("\t", string.Empty);
        // Remove repeating spaces because browsers ignore them
        result = System.Text.RegularExpressions.Regex.Replace(result,
                                                              @"( )+", " ");

        // Remove the header (prepare first by clearing attributes)
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*head([^>])*>","<head>",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"(<( )*(/)( )*head( )*>)","</head>",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(<head>).*(</head>)",string.Empty,
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // remove all scripts (prepare first by clearing attributes)
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*script([^>])*>","<script>",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"(<( )*(/)( )*script( )*>)","</script>",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        //result = System.Text.RegularExpressions.Regex.Replace(result,
        //         @"(<script>)([^(<script>\.</script>)])*(</script>)",
        //         string.Empty,
        //         System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"(<script>).*(</script>)",string.Empty,
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // remove all styles (prepare first by clearing attributes)
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*style([^>])*>","<style>",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"(<( )*(/)( )*style( )*>)","</style>",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(<style>).*(</style>)",string.Empty,
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // insert tabs in spaces of <td> tags
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*td([^>])*>","\t",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // insert line breaks in places of <BR> and <LI> tags
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*br( )*>","\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*li( )*>","\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // insert line paragraphs (double line breaks) in place
        // if <P>, <DIV> and <TR> tags
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*div([^>])*>","\r\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*tr([^>])*>","\r\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<( )*p([^>])*>","\r\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // Remove remaining tags like <a>, links, images,
        // comments etc - anything that's enclosed inside < >
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"<[^>]*>",string.Empty,
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // replace special characters:
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @" "," ",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&bull;"," * ",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&lsaquo;","<",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&rsaquo;",">",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&trade;","(tm)",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&frasl;","/",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&lt;","<",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&gt;",">",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&copy;","(c)",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&reg;","(r)",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        // Remove all others. More can be added, see
        // http://hotwired.lycos.com/webmonkey/reference/special_characters/
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 @"&(.{2,6});", string.Empty,
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // for testing
        //System.Text.RegularExpressions.Regex.Replace(result,
        //       this.txtRegex.Text,string.Empty,
        //       System.Text.RegularExpressions.RegexOptions.IgnoreCase);

        // make line breaking consistent
        result = result.Replace("\n", "\r");

        // Remove extra line breaks and tabs:
        // replace over 2 breaks with 2 and over 4 tabs with 4.
        // Prepare first to remove any whitespaces in between
        // the escaped characters and remove redundant tabs in between line breaks
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(\r)( )+(\r)","\r\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(\t)( )+(\t)","\t\t",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(\t)( )+(\r)","\t\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(\r)( )+(\t)","\r\t",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        // Remove redundant tabs
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(\r)(\t)+(\r)","\r\r",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        // Remove multiple tabs following a line break with just one tab
        result = System.Text.RegularExpressions.Regex.Replace(result,
                 "(\r)(\t)+","\r\t",
                 System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        // Initial replacement target string for line breaks
        string breaks = "\r\r\r";
        // Initial replacement target string for tabs
        string tabs = "\t\t\t\t\t";
        for (int index=0; index<result.Length; index++)
        {
            result = result.Replace(breaks, "\r\r");
            result = result.Replace(tabs, "\t\t\t\t");
            breaks = breaks + "\r";
            tabs = tabs + "\t";
        }

        // That's it.
        return result;
    }
    catch
    {
        MessageBox.Show("Error");
        return source;
    }
}









For更多信息选中此项(将HTML转换为纯文本):



[]



我希望这会对你有所帮助。





For more info Check this (Convert HTML to Plain Text) :

Convert HTML to Plain Text[^]

I hope this will help to you.



这篇关于HTML文本到纯文本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!

08-06 23:47