iterating through GridView and trying to figure out how to check if the check box controlled is enabled or not ??

How can I check if my check box control is enabled or not? I have tried the following code check :
if(inputList[i].disabled) {  }

But it does not work, because there is not a "disabled" property for my check box control.

The GridView was created dynamically in asp.net but ultimately I need to be able to set the values using Java script. All the code below works great except I don't know how to check if the checkbox is enabled or not? My goal is to check the checkbox if it is indeed disabled.

function UncheckAll(objectRef)
{

  var row = objectRef.parentNode.parentNode;
  var GridView = row.parentNode;
  var inputList = GridView.getElementByTagName("input");
  

 for(var i = 0; i < inputList.length; i++)
  {
     if(inputList[i].type == "checkbox")
	{
          if(inputList[i].disabled) // .disabled is not a property, so how can I check if it is enabled or not?
          {

          }
	  
	}


  }


}