Converting String to a number

[mxnmx]

I'm writing a pogram, a simple one that calculates certain number -which works like this...

User enters any number in a textBox
and on click of the command button the number should be incremented by 1.

Its working but if I enter 001 into textbox it returns 2 on clicking command1...please help...I want it to be 002

Here's my code:
Dim nu As Long
nu = Val(Text1.Text)
MsgBox nu