I am linking my login js file(log.js) into this html code,but it does not make any change

Question

This is my .html body content:

<form name="login"> 
    <table border="0" cellpadding="2.0" cellspacing="2.0" align="left"> 
        <tr>
            <td>Username&nbsp;</td>
            <td>
                <input name="username" type="text" id="username" maxlength="15"></input>
            </td> 
        </tr> 
        <tr>
            <td>Password&nbsp;</td>
            <td>
                <input name="password" type="password" id="password" maxlength="10"></input>       
            </td> 
        </tr> 
        <tr>
            <td>&nbsp;</td> 
            <td>&nbsp;</td> 
        </tr> 
        <tr>
            <td>&nbsp;</td>
            <td>
                <strong>
                    <input name="Login" type="button" value="Submit" onclick="Vlogin()"></input>
                </strong>
            </td> 
        </tr> 
    </table> 
</form>

...and javascript code:

function Vlogin()
{
    var user=document.login.username;
    var pass=document.login.password;
    if (user.value=="account1" && pass.value=="backup1") 
    { 
        window.location= "index.jsp";
    }
    else
        alert("Invalid username or password");
        user.focus();
    }
}

Answer 1

function Vlogin()
{
    var user=document.login.username;
    var pass=document.login.password;
    if (user.value == "account1" && pass.value == "backup1") 
    { 
        window.location= "index.jsp";
    }
    else{
        alert("Invalid username or password");
        user.focus();
    }
}

curly bracket after "else"

Answer 2

You can't access elements in your DOM by the method you are using.. such as document.login

If you want to use raw JS, you can use getElementsByTagName() https://developer.mozilla.org/en-US/docs/DOM/document.getElementsByTagName

but I suggest that you use JQuery as it's pretty much the standard

function Vlogin() {
    var login = $('form[name=login]')
    var user= $('[name=username]', login).val()
    var pass= $('[name=password]', login).val()
    if (user === "account1" && pass ==="backup1") { 
        window.location= "index.jsp";
    } else {
        alert("Invalid username or password");
        user.focus();
    }
}

I also want to point out that your validation code can easily be hacked as this will all be in plain english within your source :)