/**
 * check or uncheck all checkboxes in a form
 * Example :
 * <input type="checkbox" name="selectall" value="" 
 * onclick='xar_base_checkall(document.forms["#$module#-#$entity#-#$mode#"],"selectall_#$entity#[]",this.checked)'>
 */

function xar_base_checkall(form, field, value) {
	// count number of items
	count = 0;
	
	for (i = 0; i < form.elements.length; i++) {
		if(form.elements[i].name == field) {
			if(form.elements[i].checked != value) count++;
			form.elements[i].checked = value;
		}
	}
}