[Solved] Warning: Undefined array key

To solve Warning: Undefined array key in PHP You just need to check that what you are trying to get value exists or Not So you have to use isset. Just like this. Now, Your error must be solved. Let’s explore the solution in detail.

Solution 1: Use isset

You just need to check that what you are trying to get value exists or Not So you have to use isset. Just like this. Now, Your error must be solved.

<?php if(isset($_GET['name'])): ?>
        Your name is <?php echo $_GET["name"]; ?>
<?php endif; ?>

Solution 2: Use Ternary Operator

You can also Use Ternary Operator as a Conditional Statement. Ternary Operator syntax is (Condition) ? (Statement1) : (Statement2); We can use Just Like this.

 Your name is <?php echo  $_GET["name"] ? "Default Name" : $_GET["name"]   ?>

And now Your error must be solved.

Solution 3: Check For Null Value

Usually, This error occurs Cause Of a Null Or Empty Value So You need to use a Conditional Statement here. You can achieve this Just like the given below.

<?php if($_GET['name'] != NULL): ?>
        Your name is <?php echo $_GET["name"]; ?>
<?php endif; ?>

We can Also Use Multiple Conditions Cause the Value should be Null Or Empty So We are Going to use both Conditions in our IF.

<?php if($_GET['name'] != NULL || $_GET['name'] != ""): ?>
        Your name is <?php echo $_GET["name"]; ?>
<?php endif; ?>

And now, Your error will be solved.

Frequently Asked Questions

Summary

The solution is quite simple you need to check for null or empty values before using any variable. You can use isset(), if-else or ternary operator to check null or empty values. Hope this article helps you to solve your issue. Thanks.

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