First off you will want to set your text box to disabled. Then you will need to attach an on change event on your select element. The function that handles the on change will need to check the selected index in the select box and then remove the disabled property from the text box.
Please do your own code, not come here to ask for code. The forum is to help you fix your code, not to do your own homework...
By the way, the 'read only' means 'disable' or really means 'read only'. There are two different things. 'read only' means no user can make changes but the value of the element is still passed via form. 'disable' on the other hand, will not be passed via form.
I came to understand that you are unable to write a code for my thread. ok anyway, Am i mentioned anywhere "disabled" term in my thread. I clearly specified that it was "read-only" mode. First try to understand the thread after u can do my homework.
First try to understand the thread after u can do my homework.
I understood what 'readonly' means, but I do not do your homework. Also, if you accept Raja's solution, it means you confuse yourself with the meaning of 'readonly'. His solution is using 'disable' which is NOT 'readonly'. I just clarified the meaning of both words and hope you would get it in order to do your own homework correctly.