Thread: Replace Comma with Regex.Replace

I am trying to filter out all unwanted characters from a string. All I want in the string is letters A-Z, numbers 0-9 as well as comma (,) plus (+) and quotes (").

I figured how to do the letters and numbers, but the 3 special characters are giving me a problem. I also tried with the Chr(34) equivelant for the " sign, but no luck, as and " or , messes up the way the code is read.

Here´s what I have so far, but it only works for A-Z and 0-9:

STR = System.Text.RegularExpressions.Regex.Replace(STR, "[^A-Z, 0-9, Chr(43) ]", "")

Any ideas?

How to: Strip Invalid Characters from a String

The following code example uses the static Regex..::.Replace method to strip invalid characters from a string. You can use the CleanInput method defined here to strip potentially harmful characters that have been entered into a text field in a form that accepts user input. CleanInput returns a string after stripping out all nonalphanumeric characters except @, - (a dash), and . (a period).

Code:

 Public Function CleanInput(strIn As String) As String

        ' Replace invalid characters with empty strings.
        Return Regex.Replace(strIn, "[^\w\.@-]", "")

    End Function

Originally Posted by Tom

How to: Strip Invalid Characters from a String

The following code example uses the static Regex..::.Replace method to strip invalid characters from a string. You can use the CleanInput method defined here to strip potentially harmful characters that have been entered into a text field in a form that accepts user input. CleanInput returns a string after stripping out all nonalphanumeric characters except @, - (a dash), and . (a period).

Code:

 Public Function CleanInput(strIn As String) As String

        ' Replace invalid characters with empty strings.
        Return Regex.Replace(strIn, "[^\w\.@-]", "")

    End Function

Thanks. But I'm still having a problem leaving in " and , as if I add them to the list along with the ."- it corrupts the line.

Is there anyway I can use this regex.raplace using the Chr() code for the ASCII characters? ex. I would like to exclude all characters outside the range of Chr(33) to Chr(125)

Noone ever told you how to put a speechmark " into a string in VB?

Code:

Public Function CleanInput(strIn As String) As String

        ' Replace invalid characters with empty strings.
        Return Regex.Replace(strIn, "[^A-Z0-9,+""]", "")

    End Function

Note the double speechmark "" which does not 'break the string' because VB understands to escape this to a single speechmark

The following code MAY match outside Chr 33 to Chr 125 and replace it with nothing:

Code:

Public Function CleanInput(strIn As String) As String

        ' Replace invalid characters with empty strings.
        Return Regex.Replace(strIn, "[^\u0021-\u007D]", "")

    End Function

I say may because I've never really used the unicode specifiers; try it

Without using regex, something like:

Code:

Public Function CleanInput(strIn As String) As String
  Dim sb as New StringBuilder
  Dim lo as Char = Chr(32)
  Dim hi as Char = Chr(126)

  ForEach c as Char in strIn

    If c > lo AndAlso c < hi Then sb.Append(c)

  Next

  Return sb.ToString()

    End Function