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Check if TextBox contains anything other than an integer or comma

I have a VB.net program with a TextBox. Currently I am checking if the user typed in a space and I alert the user if the box contains a space. But I want to alert the user if anything other than an integer or comma is entered. Would there be a simple way to determine if anything other than a integer or comma have been entered? Here's the code I have for checking if a space was entered...

        If PortBox.Text.Contains(" ") Then
            MsgBox("Port box cannot contain spaces", MsgBoxStyle.Critical, "Port Error")
            Exit Sub
        End If

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SOLUTION

kaufmed

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Brian

ASKER

I'm assuming that using Regex.IsMatch is the best way to do this, but I can't figure out how to incorporate the comma when using Regex.

Brian

ASKER

käµfm³d, yes, but can I add a check for comma to that line of code?

Brian

ASKER

Also, I need to figure out if anything other than an integer or comma in the textbox. I tried using this...

       If Not Regex.IsMatch(PortBox.Text, "^[0-9,]") Then
            MsgBox("Not all integers")
        End If

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to see if there is anything other than Integers in the textbox, but of course that only checks if there is a number anyplace within the string, not that all are numbers.

ASKER CERTIFIED SOLUTION

Fernando Soto

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Brian

ASKER

It even works with commas! If I have "8,10,15", it still works, which is awesome! Does this work with commas because of the "+$"?

kaufmed

I don't understand what you mean by "but can I add a check for comma to that line of code". That's exactly what the regex I suggested does, as I elaborated upon within that same comment.

Fernando Soto

Hi Brian;

This part of the pattern, "^[0-9,]", only checks the very first character in the TextBox and does not check any other. By adding the + sign where I placed it, it will check all the characters in the string and the $ does it to the end.