var checked = new Image();
var unchecked = new Image();
var param;

function SwitchImage(param,i) {
	if (param=='box') {	
		checked.src = 'img/checked_box.gif';
		unchecked.src = 'img/unchecked_box.gif';
	}
	else  {	
		checked.src = 'img/checked_radio.gif';
		unchecked.src = 'img/unchecked_radio.gif';
	}
    if (document.getElementById('my_check'+i).checked == true) {
        document.getElementById('my_check'+i).checked = false;
        document.getElementById('check_image'+i).src = unchecked.src;
    } else {
        document.getElementById('my_check'+i).checked = true;
        document.getElementById('check_image'+i).src = checked.src;
    }
}