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();
}
} //-->
以上这篇JavaScript判断用户名和密码不能为空的实现代码就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持编程之家。
原文链接：https://www.f2er.com/js/48754.html