Keeping Leading Zeros in a Textbox - vb.net

Question

I need to keep leading zerod in a textbox that will be used to input data into a database. It is for SKU Numbers. I need to be able to type in leading zeros (ex. 001234567890) and then input them into the database.
However I can't figure out how to keep the leading zeros in a double. I do not need it in a string format but in a double. Is there a way to do this while keeping it a number and not a string?
EX.
txtProductBarcode.Text = Format(txtProductBarcode.Text, "############")
'This does not work

Answer 1

Using 0 in place of # will cause leading zeros to be output.
For example:
Dim s as string = string.Format("{0:000###}", 12345d)
Console.WriteLine(s)
will output
012345
See Pad a Number with Leading Zeros on MSDN.
BTW, not sure why you are worried about keeping the leading zeros whilst "as a double". The double is just a double, and formatting for display shouldn't matter. 0123 is the same as 123, otherwise you should be using a string datatype and not a double.

Answer 2

Try this is one.
You can convert the integer num to double.
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
Dim num As Integer
Dim temp As String = ""
Try
If Regex.IsMatch(TextBox1.Text, "^[0-9 ]+$") Then
num = Integer.Parse(TextBox1.Text)
If num <> 0 then
TextBox1.Text = num.ToString("D6")
temp = num
else
TextBox1.ReadOnly = False
End If
If num.Length = 6 Then
TextBox1.ReadOnly = True
TextBox1.BackColor = Color.White
ElseIf num = 0 Then
TextBox1.ReadOnly = False
End If
TextBox1.SelectionStart = TextBox1.Text.Length
End If
Catch ex As Exception
Msgbox(ex.Message)
End Try
End Sub