JavaScript implementation code to determine that username and password cannot be empty
<script language="javascript"><!--function VF_form1(){ //v2.0<!--start_of_saved_settings--><!--type,password,name,Password,required,true,errMsg,Password cannot be empty!--><!--type,text,name,User,required,true,errMsg,User,required,true,errMsg,User,user,end_of_saved_settings--> var theform = document.form1; var errMsg = ""; var setfocus = ""; if (theform['password'].value == "") { errMsg = "The password cannot be empty!"; setfocus = "['password']"; } if (theform['username'].value == "") { errMsg = "The username cannot be empty!"; setfocus = "['username']"; } if (errMsg != ""){ alert(errMsg); eval_r("theform" + setfocus + ".focus()"); } else { theform.submit(); }} //--></script>The above JavaScript implementation code that determines that the username and password cannot be empty is all the content I have shared with you. I hope it can give you a reference and I hope you can support Wulin.com more.