passing function parmeter

[chrisio]

Hi,
I have this really simple function and for the life of me i cant remember how to pass the fieldname which is passed in the function.

function Change(fieldName)
	{
		if(document.mainDetails.enable.checked == true) 
  			{ 
				document.mainDetails.fieldName.disabled = false; 
			}
		else
  			{
				document.mainDetails.fieldName.disabled = true;
			}
	}

put me out of my misery please.

Thanks
CHris

[Pepejeria]

Change("my_field_name");

[chrisio]

Change("my_field_name");

thanks for replying.

i am already passing the field name ok as if I do
alert(fieldName); I can see it. but how do I pass that to the
document.mainDetails.fieldName.disabled = false; line as that brings an error saying it cant find an element called fieldName

Thanks
CHris

[paul_wilkins]

document.mainDetails[fieldName].disabled = false;

[chrisio]

thanks, I was using curly brackets instead of square brackets