Front-End Form Submission in Shortcode

The plugin I am working on contains shortcodes with forms on them. Upon form submission (POST), I do some database work, and then planned on redirecting to another page after the db work is complete. When I attempt this, I get the “Headers Already Sent” warning. Within the shortcode function, how do I call my redirect sooner than get_headers? Do I need to use some separate callback function?

Answers:

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Method 1

You have to hook an earlier action to check if the form was submitted. Something like:

function wpa_process_form(){
  if( isset( $_POST['my_form_data'] ) ){
      // process form and redirect
  }
}
add_action( 'init', 'wpa_process_form' );

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