怎么实现提交两表单 怎么实现一个表单提交到两个页面

<script   language="javascript">   
function   check()   
{   
var   form=document.all.form1   
if(form.username.value=="")   
{   
alert("不能为空！")   
form.username.focus()   
return   false;   
}   
form.action="1.html"   
form.submit()   
form.action="2.html"   
return   true;   
}   
</script>   
<form   name="form1"   method=post   onsubmit="return   check()"   target="_blank">   
<input   type="text"   name="username">   
<input   type="submit">   
</form>

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