dataformat.html

<html>
    <head>
     <title>datavalidiation</title>
     <script type="text/javascript">
     function validiate()
     {
         var uname=document.getElementById("uname");
         var pass=document.getElementById("pass");

         if(uname.value.trim()=="")
         {
             alert("blank username");
             uname.style.border="solid 3 px red";
             return false;
         }
         else if(pass.value.trim()=="")
         {
           alert("blank password");
           return false;
         }
         else if(pass.value.trim().length<5)
         {
             alert("password is too short");
             return false;
         }
         else{
             return true;
         }
     }         
      
     </script>
    </head>
    <body>
     <form onsubmit="return validiate()";
      action="message2.html">
      <input id="uname" placeholder="username" type="text"/><br><br>
      <input id="pass" placeholder="password" type="password"/><br><br>
      <button onclick="validiate()" type="submit">submit</button>  
     </form>
    </body>
</html>