PHP Notice: Undefined index: in a line

Question

I know a lot of people have asked this question but mine is not working with:

if(isset($instance['threadnumbers'] == "")){ $instance['threadnumbers'] == "" }

It shows a debugging errors on:

PHP Notice: Undefined index: threadnumbers in /home/content/59/12158859/html/development/wp-content/plugins/dpt/disqus-ptw.php on line 27

And that area is below:

if ($instance['threadnumbers'] == NULL) {
    $instance['threadnumbers'] = "5";
}

How to fix it? Thanks a lot :)

Answer 1

You have a cut and paste error. You are trying to assign a value using a comparison operator. == should be = .

You also are using isset() on an assignment.

if(isset($instance['threadnumbers'])){ $instance['threadnumbers'] == "" }

should be

if(!isset($instance['threadnumbers']) || empty($instance['threadnumbers'])) { 
    $instance['threadnumbers'] = ""; 
}

Answer 2

Replace

if(isset($instance['threadnumbers'] == "")){ $instance['threadnumbers'] == "" }

With

if(isset($instance['threadnumbers'])){ $instance['threadnumbers'] = "" }

isset will return true or false . When you loose compare it ( == ), false will equal "" .

Also, $instance['threadnumbers'] == "" should be $instance['threadnumbers'] = "" , because you want to assign an empty string to the variable.