Question

I would like to select certain elements in form by their name, so I suppose using getElementsByName(name). Then I would like to add a value to these elements. How do I do this loop?

boxesEL = document.getElementsByName(boxesName);

for(var x=0;x<=boxesEL.length;x++){
    boxesEL[x].value = "some value";
}

I’m getting an error boxesEL[x] is undefined.

Answer 1

Take out the “=” sign in the comparison in the for loop. You’re looping one too many times. Length gives you the number of elements – the maximum index of the collection will be one less, because it’s zero based.

for(var x=0; x < boxesEL.length; x++)   // comparison should be "<" not "<="
{
    boxesEL[x].value = "some value";
}