I have set the MaxLength property of a textbox in my windows forms application to 10

I am populating the textbox by reading from a file. However if a read string which is more than 10 characters the textbox still gets populated. But when I manually try to enter a string it works fine (that is, it does not allow more than 10 characters to be entered).

Why is there a difference between these two behaviors? How can I populate my textbox from the file and still have the MaxLength property to be working?

Thanks,
Viren