JavaScript判断用户名和密码不能为空的实现代码

<script language="javascript"><!-- function VF_form1(){ //v2.0 <> <> <> <> var theform = document.form1; var errMsg = ""; var setfocus = ""; if (theform['password'].value == "") { errMsg = "密码不能为空!"; setfocus = "['password']"; } if (theform['username'].value == "") { errMsg = "用户名不能为空!"; setfocus = "['username']"; } if (errMsg != ""){ alert(errMsg); eval_r("theform" + setfocus + ".focus()"); } else { theform.submit(); } } //--> </script>

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