How to strip HTML and special character from string.

I have created following function to strip or remove HTML and specail character from string.
Regular Expression for special character:([^\w\+\-\\\/_ ])
Regular Expression for HTML strip:<(.\n)+?>

-------------Code--------------------
public static string StripHTMLAndSpecialChars(string sHTML)
{
string strOutput = StripHTML(sHTML);
System.Text.RegularExpressions.Regex objRegExp = new System.Text.RegularExpressions.Regex(@"([^\w\+\-\\\/_ ])");
//Replace all characters other than ones specified above
strOutput = objRegExp.Replace(strOutput, "");
objRegExp = null;
return strOutput;
}

----------------Function to strip HTML-----------------
public static string StripHTML(string sHTML)
{
string strOutput;
System.Text.RegularExpressions.Regex objRegExp = new System.Text.RegularExpressions.Regex("<(.
\n)+?>", System.Text.RegularExpressions.RegexOptions.IgnoreCase);
//Replace all HTML tag matches with the empty string
strOutput = objRegExp.Replace(sHTML, "");
objRegExp = null;
return strOutput;
}

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