var checkType = "false";
function tbSelectAll(){
	var checkItem = 0;
	for(var i = 0 ; ; i++){
		if(document.getElementById("cn_tablebean_check_"+i+"_0") != undefined){
			checkItem = i
		}else{
			if(checkType == "true"){
				for(var j = 1 ; j < checkItem + 1 ; j++){
				  document.getElementById("cn_tablebean_check_"+j+"_0").checked = false;
				  checkType = "false";
				}
			}else{
				for(var j = 1 ; j < checkItem + 1 ; j++){
				  document.getElementById("cn_tablebean_check_"+j+"_0").checked = true;
				  checkType = "true";
				}
			}
			break;
		}
	}
}