WinForms TextBox that splits at a specified interval


I don’t know that this code is all that useful for anyone, but I thought I’d share it as opposed to just deleting it. It was something I put together in 5 minutes to answer a question on the MSDN forums:

    ''' <summary>
    ''' TextBox that will put a carriage return in every set amount of characters (in the WrapAtInterval property)
    ''' </summary>
    ''' <remarks>5-5-2011 - blakepell</remarks>
    Public Class TextBoxEx
        Inherits TextBox
     
        Sub New()
     
        End Sub
     
        Private Sub TextBoxEx_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles Me.KeyPress
            If Me.Text.Length = 0 Then
                Exit Sub
            End If
     
            ' The key hasn't been inserted into the text box at this point, so we need to add
            ' a + 1 to it so the length we check is the length that will be in the box.  We need
            ' to get rid of the hidden characters that don't actually show while checking the length.
            Dim buf As String = Me.Text.Replace(vbCrLf, "").Length + 1
     
            If (Me.Text.Replace(vbCrLf, "").Length + 1) Mod Me.WrapAtInterval = 0 Then
                ' Now, we know we are on a interval of what is set in the property "WrapAtInterval".  So, whenever that interval is
                ' hit, we will execute this code
     
                ' First, save the position in the text box.
                Dim currentPos As Integer = Me.SelectionStart
     
                ' Second, add the key and the carriage return.  Then tell the text box that you handled adding it yourself and not
                ' do also add it.
                e.Handled = True
                Me.Text += e.KeyChar & vbCrLf
     
                ' Third, put the cursor back now that we've updated the text property, we'll add 3 characters to it for the vbCrLf which
                ' is a carriage return AND a line feed (ASCII 13 & 10)
                Me.SelectionStart = currentPos + 3
     
            End If
     
        End Sub
     
        Private _wrapAtInterval As Integer = 5
        
        Public Property WrapAtInterval() As Integer
            Get
                Return _wrapAtInterval
            End Get
            Set(ByVal value As Integer)
                _wrapAtInterval = value
            End Set
        End Property
     
    End Class

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