Question

I’m trying to ensure that all characters which are not numeric, or alphabetic are converted to HTML code when submitted to my database.

With a bit of Googling, I have come up with this:

Public Shared Function HTMLEncodeSpecialChars(text As String) As String
    Dim sb As New System.Text.StringBuilder()

    Dim i As Integer
    Dim charArray() As Char = text.ToCharArray()
    ' display contents of charArray
    For i = 0 To charArray.Length - 1
        sb.Append((String.Format("&#{0};", Asc(charArray(i)))) & ",")
    Next
    Return sb.ToString()
End Function

This successfully converts anything to HTML, but now I need to put some condition in there so it only does it where I need it to. ie; on any character which will either screw up my database entry, or screw up formatting when returned back to the screen as HTML (this database content is for product data for a website).

So for simplicity, I guess I want to convert only charcters which are not A-Z alphabetic or 1-0 numeric.

I could use isNumeric, but not sure how to detect alphabetic characters.

I’ve been Googling and found something which looked like it would work, but the logic/filtering was wrong.

So I figured I’d ask here 😀

Answer 1

You haven’t said why existing tools don’t work for you, so you might not know about this:

HtmlEncode method in the System.Web namespace:

HTML encoding makes sure that text is displayed correctly in the
browser and not interpreted by the browser as HTML.