Hi Guys

i have a formValidation Java Script on the form to validate username and password
text boxes to check whether they are empty,and i am calling them on the Onclient Click
even ton the button, But even If i enter some data into those text boxes the error message
alert appears, what it the problem with my code here ?

`<script type="text/javascript">

function FormValidator() 
    if (document.getElementById('txtusername').value == "");

        alert('Invalid User Name');


     if (document.getElementById('txtpassword').value == "");

        alert('Invalid Password');





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how we can a field validate from database? like when i enter in user abc it validat from database whether valid or not?

In HTML5 you can use attribute "required" to <input type="text" required="required" /> and <input type="password" required="required" /> instead of your js function

i thin u not pick my point. i want to validate a field whether a valid user mean when i enter in user fied abc whether this abc is in the database table or not if yes then ok othere wise it give alert.....

var txtusername = document.getElementById('txtusername').value;
    function(data){return data;});

and index.php

    /* check in db $_POST['isitinDB'] and return true or false */