Advise on algorithm

Question

Hello,
Having a very strict controlled multiline TextBox, using KeyPress to allow alphabets and numbers plus CTRL + C/V and Enter

To control what is pasted I also use TextChanged with a loop from 0 to TextBox.TextLength to evaluate and omit each unwanted character:
For MyLoop = 0 To MessageTextBox.TextLength - 1
Select Case Convert.ToInt32(MessageTextBox.Text.Chars(MyLoop))
Case 32, 45, 46, 48 To 57, 64, 65 To 90, 97 To 122, 13
FileNameFilter = FileNameFilter + MessageTextBox.Text.Chars(MyLoop)
End Select
Next
MessageTextBox.Text = FileNameFilter

Everything is working fine except Enter, which will not survive the TextChanged event check!

Not sure if doing it the best way possible, but how can I also get Enter to work?
Thank you for helping out

Answer 1

Hi @OSVBNET ,
If you want to use the Enter key to wrap lines, you need 10 instead of 13.

    Private Sub MessageTextBox_TextChanged(sender As Object, e As EventArgs) Handles MessageTextBox.TextChanged  
        Dim FileNameFilter As String = ""  
        For MyLoop = 0 To MessageTextBox.TextLength - 1  
            Select Case Convert.ToInt32(MessageTextBox.Text.Chars(MyLoop))  
                Case 32, 45, 46, 48 To 57, 64, 65 To 90, 97 To 122, 10  
                    FileNameFilter = FileNameFilter + MessageTextBox.Text.Chars(MyLoop)  
            End Select  
        Next  
        MessageTextBox.Text = FileNameFilter  
        MessageTextBox.SelectionStart = MessageTextBox.TextLength  
    End Sub  

Best Regards.
Jiachen Li

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