What is the checkbox array in the DOM?

Posted on 2004-08-16
Last Modified: 2011-10-03
I have a form with a couple of listboxes and a lot of checkboxes.  I am looking to make all of these checkboxes unchecked.

for (var i=0; i<document.form.checkbox.length; i++)
  document.form.checkbox[i].checked = false;

However, whenever I run this, I get an error that says that document.form.checkbox.length is null or not an object.

The only thing I can think of is that checkbox is not the array in the DOM that I am looking for.

What is the correct syntax for this?

BTW  The checkboxes are not the same name, nor can they be the same name.
Question by:light777
LVL 15

Expert Comment

ID: 11814680
try this

for( intIndex = 0; intIndex < document.formname.length; intIndex++ )


   if( document.formname[ intIndex ].type  == "checkbox" )
      document.formname[ intIndex ].checked = false;


for( intIndex = 0; intIndex < document.all.length; intIndex++ )


     if( document.all( intIndex ).type == "checkbox" )
          document.all( intIndex )checked = false;

Accepted Solution

MrClean21 earned 125 total points
ID: 11814687
Here's a technic to uncheck all checkboxes.

for (var c = 0; c < document.form.elements.length; c++)
   if (document.form.elements[c].type == 'checkbox')
      document.form.elements[c].checked = false;


Author Comment

ID: 11814739
Thanks, that works perfectly

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