dropdown control..

hi..

 

i am having four dropdown controls and a textbox in my form, i want to bind the field of the table to it and when i select the item from the dropdown control its corresponding price is shown into the textbox, now again i select any item from the second dropdown control, its corresponding price is added with the first items price and total price of both the item is shown in the textbox.

 

plz help me on this prob..

 

thanks everyone..
...