前臺的html

  //form表單
      <iframe name="myform" id="myform" frameborder="0" src="" style="display:none;"></iframe>
	<div class="popCon">
		<form  method="post" action="?act=add" target="myform">
			<fieldset>
				<input type="text" name="username" id="username"/>
				<input type="text" name="phone" id="phone"/>
			</fieldset>
		</form>
	        <a class="close jqmClose" href="javascript:void(0)" title="關閉">關閉</a>
	</div>
 

後臺的php檔案

  alert("恭喜您已成功提交留言資訊，稽核中......");
 function alert($str, $exit = false) {
    echo '<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />';
    echo '<script language="javascript">window.alert("' . $str . '");</script>';
    $exit && exit ();
}