converting from any base(16, 8, 2) to base 10 in C#

Question

Hi there, Could anyone help me with the following problem ? Suppose I have a textBox in which there can be introduced any string representing a number in one of the following bases: 16, 8, 2 Suppose again that I have more radio buttons : hex, dec, oct, bin. When one of them is checked the number written in the textBox would be converted to the proper base (hex - to hexadecimals, etc.) I want to convert the number in the textBox to base 10 (of course the modified number will be displayed in the textBox). The function that performs the conversion to base 10 doen't know the initial number's base ! How can I do this ? Please help me ! Please answer by tomorrow ! I've searched the net and found nothing appropiate ! :( I'm in desperate need of help !:( Thankx . Cheers, Adisor P.S. To those who celebrate Easter I wish them : Happy Easter !!! :)