Required field validator for textbox fire on selecting checkbox

Hi,


1) I have a checkbox control chk1,listbox control lst1 and textbox control txtOther.

 If the user selects the checkbox chk1 ,there is a list box next to it.The user has to select an item from the listbox.

 If the selected item is Other ,then the user has to enter a value in the texttbox for the Other option selected .Otherwise,if any item is

selected than other,there is no need to enter value in the texbox.

So basically I should have required field validator  for listbox and textbox.

The requiredvalidator vallst1(for listbox) should fire only if chk1 is selected.

The requiredvalidator valtxtOther(for textbox) should fire only if Other item is selected from the listbox.

 

2)I also have another chk2 checkbox control  and 2 textbox controls

If user selects chk2 ,required field validator controls should fire for 2 textbox controls.

I have to impl ...