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WordPress WordPress Hooks - Actions and Filters Filter Functions in WordPress The apply_filters Function

Yohan Park
Yohan Park
7,148 Points

Why tie apply_filters to a value?

when using apply filter we echo out a value that is equal to apply filters. at 1:25

echo $value = apply_filters( …)

why do that instead of

echo apply_filters()

what's the importance?

Ryan Dainton
Ryan Dainton
17,164 Points

Hi Yohan

My understanding is that you will not always want to echo out the results of your apply_filters() method, and so it's best to save it as a variable which can then be echo'd when required.

For example, looking at the 'wp_title' Hook, the filter is applied, but the result is only echoed to the screen if $display === true.

$title = apply_filters( 'wp_title', $title, $sep, $seplocation );
if ( $display ) {
        echo $title;
    } else {
        return $title;

1 Answer

Yohan Park
Yohan Park
7,148 Points

That makes a lot of sense. Thank you, Ryan.