互动交流的搜索点击后跳转本页，大神看看哪里不对 [复制链接]

<form method="get" action="/index.aspx" name="letter">
    <img alt="" width="21" height="22" src="/e/images/diy/letter_search_icon.jpg" /> <strong>信件进度查询</strong>&nbsp;&nbsp;&nbsp;&nbsp; 查询码：<input id="code" class="tb" size="13" name="code" type="text" />&nbsp;&nbsp;&nbsp;姓名：<input id="pa_name" class="tb" size="13" name="pa_name" type="text" /> <input type="hidden" name="modelid" value="74" /><input type="hidden" name="lanmuid" value="50" /><input type="hidden" name="sublanmuid" value="373" /><input type="hidden" name="siteid" value="1" /><input type="hidden" name="search" value="1" /> <input align="absBottom" src="/e/images/diy/letter_search.jpg" width="41" height="20" type="image" onclick="return cs()" longdesc="undefined" />
</form>
<script type="text/javascript">
function cs()
{
   if(document.letter.code.value=="")
    {
     alert("请输入查询码!");
     document.letter.code.focus();
     return false;
    }
   if(document.letter.pa_name.value=="")
    {
     alert("请输入您的姓名!");
     document.letter.pa_name.focus();
     return false;
    }
   return true;
}
</script>
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