Char Array Console.WriteLine Regex.Replace

`Remove` HTML

Often we encounter Strings that contains HTML markup. It is possible to remove this markup with a custom VB.NET Function.

We develop a custom Function based on the Regex type. It uses a regular expression to strip HTML markup tags—this works on many source strings.

An example

To begin, this program introduces the StripTags Function, which performs the HTML removal. This calls the Regex.Replace function.

Note In StripTags() all text matching a tag start character and ending with a tag end character is replaced with an empty string.

Note 2 In Main() we declare a String literal that contains HTML markup. Next, the StripTags function is invoked with that String as the argument.

Finally We demonstrate that the resulting string has no HTML markup remaining by printing it to the Console.

Imports System.Text.RegularExpressions

Module Module1

    Sub Main()
        ' Input.
        Dim html As String = "<p>There was a <b>.NET</b> programmer " +
            "and he stripped the <i>HTML</i> tags.</p>"

        ' Call Function.
        Dim res As String = StripTags(html)

        ' Write.
        Console.WriteLine(res)
    End Sub

    ''' <summary>
    ''' Strip HTML tags.
    ''' </summary>
    Function StripTags(ByVal html As String) As String
        ' Remove HTML tags.
        Return Regex.Replace(html, "<.*?>", "")
    End Function

End Module
There was a .NET programmer and he stripped the HTML tags.

A warning

If you have HTML markup that is malformed in any way, or has comments, this method will not work. You may wish to first validate the markup.

Tip You can validate HTML markup using a simple parser that matches tag characters.

The easiest way to strip HTML tags is to use the Regex type. Other methods that scan the String and use Char arrays are more efficient, but will also be more complicated.