jQuery : 判斷radio有無選取 (check radio type is checked)

html

<input id="labt1" type="radio" name="LABTYPE" name="LAB" value="1" >LAB1
<input id="labt2" type="radio" name="LABTYPE" name="LAB" value="2" >LAB2


--------------------------------------------

JavaScript

if(typeof($("input[name=LABTYPE]:checked").val()) === "undefined" )
{
alert("請選擇LAB");
return false;
}