Remove all HTML tags or retrieve text matching HTML tags

Use regular expressions to operate HTML tags
// Retrieve the value of the matching item in the specified HTML Tag. regexoptions. ignorecase is case-insensitive, and regexoptions. multiline is case-insensitive.
Match titlematch = RegEx. match ("<title> webform3 </title>", "<title> ([^ <] *) </title>", regexoptions. ignorecase | regexoptions. multiline );
// Retrieve the value of the first matching item
String tmpstrtitle = titlematch. Groups [1]. value;
// Replace all HTML tags on the HTML page
Label1.text = RegEx. Replace (label1.text. Trim (), "<. +?> "," ") +" ********* "+ Titlematch. Groups [1]. value;
String tmpstr = string. empty;
// Determine whether the matching regular expression is successful
If (RegEx. Match (tmpstr, "<. +?> "). Success)
{
// Operation
}