//控制TextBox TextMode="MultiLine" 字數限制
function isMaxlength(obj, size) {
	var mlength = obj.getAttribute ? parseInt(obj.getAttribute("maxlength")) : ""
	if (obj.getAttribute && obj.value.length > mlength) {
		obj.value = obj.value.substring(0, mlength)
		alert('字數限制' + size + '字唷！');
	}
}