<input type = "button" class = "myBtn" name="selectbtn" value = "選定" onClick="selectgoods_on2()" >
setBtnDisable(myform.selectbtn);
setBtnEnable(myform.selectbtn);
function setBtnDisable(obj){
obj.setExpression("disabled", "true");
}
function setBtnEnable(obj){
obj.setExpression("disabled", "false");
}