Disable combo box value once selected

[ajju1987]

Hii
I fetched value from database and attach to combobox.. further from the option selected i displayed certain values in the grid..
I want if a user select any value from combobox then I want that he will not able to select it again... How it is possible
Reply plz...
if anyone can mail me solution thanks in advance.. my project work is stopped due to this..

[BRawn]

If I'm understanding this correctly, you want to keep the value of the displayed item in the combobox but when you select the item, the application must do nothing with it as it will be disabled?