Undefined Variable With Form Validation

[grahamgr3 1]

In the following code I am validating a url in a practice page I am using from the stuff I learned in the book­. When I enter an invalid url in my form, I get an $url undefined error when running the code below. I am guessing the error is pretty easy to spot, but I am new at this. 

 

if (filter_var($scrubbed['url'], FILTER_VALIDATE_URL)){

$url = mysqli_real_escape_string($dbc, $scrubbed['url']);

} else {

echo '<p class="error">Please enter a valid url</p>';

}

[HartleySan 826]

Because the $url variable is only defined when the if conditional is met. If the else branch is executed instead, then the $url variable never exists.

[grahamgr3 1]

How could I rephrase this if else condition so that it would make sure $url is defined.

[HartleySan 826]

Add $url = ''; below the echo statement within the else block.