Saya telah menghadapi masalah serupa dan menemukan solusi terbaik. Kode di bawah ini berfungsi sempurna untuk saya.
private string ConvertHtml_Totext(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,
@"•"," * ",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"‹","<",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"›",">",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"™","(tm)",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"⁄","/",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"<","<",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@">",">",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"©","(c)",
System.Text.RegularExpressions.RegexOptions.IgnoreCase);
result = System.Text.RegularExpressions.Regex.Replace(result,
@"®","(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;
}
}
Karakter melarikan diri seperti \ n dan \ r harus dihapus terlebih dahulu karena menyebabkan ekspresi reguler berhenti berfungsi seperti yang diharapkan.
Selain itu, untuk membuat string hasil ditampilkan dengan benar di kotak teks, seseorang mungkin perlu membaginya dan menyetel properti Garis kotak teks alih-alih menetapkan ke properti Teks.
this.txtResult.Lines = StripHTML (this.txtSource.Text) .Split ("\ r" .ToCharArray ());
Sumber: https://www.codeproject.com/Articles/11902/Convert-HTML-to-Plain-Text-2