js防止按鈕重複送出內容

[script type="text/javascript"]

function submitForm() {
document.formname.button.disabled = true;
submitForm = disableButton;
document.formname.submit();
return false;
}
function disableButton() {
alert('In processing');
return false;
}

[/script]

[form name="formname" action="xxx.cgi" method="post"]
[button name="button" onClick="submitForm()"]SUBMIT[/button]
[/form]