Enable/disable Input Fields With Checkboxes (javascript)

I'm trying to make a html5 form with different input fields, with a checkbox that can enable/disable input fields. When the checkbox is selected, it should be possible to enter dat

Solution 1:

You check the state of the checkbox

document.getElementById("inputfield").disabled= this.checked;

Solution 2:

Thanks! Also got another solution:

functionactive()
{
  if(document.getElementById('checkbox').checked)
     document.getElementById('inputfield').disabled=false;

  elsedocument.getElementById('inputfield').disabled=true;
}