Is there a way of making strings file-path safe in c#?

Ugh, I hate it when people try to guess at which characters are valid. Besides being completely non-portable (always thinking about Mono), both of the earlier comments missed more 25 invalid characters.

foreach (var c in Path.GetInvalidFileNameChars()) 
{ 
  fileName = fileName.Replace(c, '-'); 
}

Or in VB:

'Clean just a filename
Dim filename As String = "salmnas dlajhdla kjha;dmas'lkasn"
For Each c In IO.Path.GetInvalidFileNameChars
    filename = filename.Replace(c, "")
Next

'See also IO.Path.GetInvalidPathChars