Question

I have the following form in my index.php page

    <form action='login.php' method='POST'>
    Log in Here:<br><br>
    Username:<input type='text' name='User_name' value='username' onFocus="clearText(this)" id='fn'>
    <br><br>
    Password:<input type='password' name='_password' ><br><br>
    <input  value='Log in' type="image" src="client-login-buttonclient-login-button.jpg" ><br><br>
    <input type="checkbox" name="checkbox"  id="checkbox" />
    Remember password</span></p>
    </form>

and I am posting the form fields to another php page called login.php

  <?php

    session_start();
    $username=$_POST['User_name'];
    $password=$_POST['_password'];
    if($username && $password){
    echo $username;
    echo $password;
    }
    else {
    echo 'A field is empty';
    }

But when I do this, it gives me the following error

 Notice: Undefined index: User_name in login.php on line 4
 Notice: Undefined index: _password in login.php on line 5

Why is the post method not working?

Answer 1

The error indicates that the variables are not being passed. In order to bypass the error and still catch that a field is blank, utilize isset():

$username = (isset($_POST['User_name']) ? $_POST['User_name'] : '');

This will check to see if the variable was passed and if so, then set the corresponding variable to that value, otherwise set it as ” (or another value of your choosing).