check_ajax_referer

The check_ajax_referer function in WordPress is used to verify the nonce (number used once) sent in an AJAX request. Nonces are used to ensure that a request is coming from an authorized source and is not a malicious attack.

This function checks to make sure that the nonce is valid and matches the expected value. If the nonce is valid, the function returns true. If the nonce is not valid, the function will stop the execution and return an error message.

The check_ajax_referer function is commonly used in WordPress plugins that handle AJAX requests, such as form submissions or dynamic content loading.

Here is an example usage code:

if ( isset( $_POST['my_form_data'] ) && check_ajax_referer( 'my_form_nonce', 'nonce_field' ) ) {
    // Process the form data
} else {
    // Return an error message
}

In this example, the check_ajax_referer function is used to verify the ‘my_form_nonce’ nonce sent in an AJAX request. If the nonce is valid, the code inside the if statement will be executed. Otherwise, an error message will be returned.

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