How to add Event with Text Box.



I am makign a Block like this----


 Subject ------

 Customer -----omi


In my block…

I want to add a onchange event with first select box,  which ID is ‘akg’.

 when i changed the value in select box(ID=akg)  this is give me error , object expected.

i am declaring the method like this-


can you help me,    please tell me, how i can add onchange event with a select BOX



In which place of code you are declaring " de:function(){" ?
When you are using function name inside onchange method you need to use global names. So function must be declared on top level as

function de(){ … }

or you need to use full name as