Check CheckBox

I have a page that displays records returned from a database and places a check box
next to each record that the end user can check if they want to delete a record.
The function below checks to make sure that at least 1 checkbox was checked before allowing the delete to be processed.

this function works just fine when I have more than 1 recored returned, but if I only have 1 record displayed on the page and check it and hit the delete button, I get this error

"Checked" is null or not an object

is there a way to modify the function to fix this problem.

function isCheckBoxChecked(boxgrp)
// This function is used to check if any check boxes
// are checked before processing
{
var i = boxgrp.length;
do
if (boxgrp[--i].checked)
return true
while (i);
alert('Select an Item to Delete');
return false
}