TextBox.SelectAll() does not justify text to left in silverlight

I have given a fixed width to the textbox and I don't want to wrap the text too. So the problem here is if I enter text larger then the width then on GotFo开发者_运维百科cus event of a textbox I do the following :

txtperson.SelectAll();

But it doesn't justify the text from left ? Any help how can I achieve this ?

---

Well, what you can easily do is to retemplate your textbox. when it gets focus you just change background color of the text and it will does the trick.