[WordPress/Trust Form] 一部の入力フィールドの値をcookieに保存し、次回入力時に読み込む

functions.php

<?php
function save_trustform_default_value() {
	if (isset($_REQUEST['tr_default_3']) && $_REQUEST['tr_default_3'] == 1) {
		$data = array();
		$trust_form = new Trust_Form_Front(3);
		$col_name = $trust_form->get_col_name();
		foreach ( $col_name as $key => $name ) {
			if ($name == '保存したいフィールドのラベル') {
				$data[$key] = stripslashes_deep($_POST[$key]);
			}
		}
		setcookie('wordpress_tr_default_3', serialize($data), time()+3600);
	}
}
add_action( 'wp_loaded', 'save_trustform_default_value' );

trust-form-tpl-3.php

<?php
function trust_form_show_input() {
	global $trust_form;
	
	$col_name = $trust_form->get_col_name();
	$validate = $trust_form->get_validate();
	$config = $trust_form->get_config();
	$attention = $trust_form->get_attention();
	
	// set default value from cookie
	$data = unserialize( stripslashes_deep($_COOKIE['wordpress_tr_default_3']) );
	if (isset($data) && is_array($data)) {
		foreach ($data as $key => $name) {
			$_POST[$key] = esc_attr($name);
		}
	}
	
	$nonce = wp_nonce_field('trust_form','trust_form_input_nonce_field');

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