php字符串在echo div标签内

Question

I'm trying to add a return policy custom field just above the add to cart button in woocommerce. I've got the following function:

<?php
add_action( 'woocommerce_single_product_summary', 'return_policy', 20 );
function return_policy() {
    echo '<div id="return-policy-wrapper">
            <?php the_cfc_field('rp-info-meta', 'rp-info-custom-filed'); ?>
          </div>';
}

But the code validator points out there is an error somewhere in the string. I suspect the the error is with the single quote marks inside <?php the_cfc_field('rp-info-meta', 'rp-info-custom-filed'); ?> <?php the_cfc_field('rp-info-meta', 'rp-info-custom-filed'); ?>

I changed the single quotes in that string for double quotes. Now the string validation error is gone, but the function won't work.

Are they the single quotes that are causing the error and how can I fix it?

Answer 1

You're already in a <?php ... ?> context. Simply build your string. For example

printf('<div id="return-policy-wrapper">%s</div>',
        get_cfc_field('rp-info-meta', 'rp-info-custom-filed'));

or

echo '<div id="return-policy-wrapper">',
     get_cfc_field('rp-info-meta', 'rp-info-custom-filed'),
     '</div>';

Note, I've used get_cfc_field instead so the string is returned and not echo -ed directly.

---

Another approach would be

echo '<div id="return-policy-wrapper">';
the_cfc_field('rp-info-meta', 'rp-info-custom-filed'); // this echoes the value
echo '</div>'

Answer 2

The script is in the quoted string passed to the echo command, and is therefore not treated as a script, but echoed along with the rest of the string.

This might work as intended:

<?php
add_action('woocommerce_single_product_summary', 'return_policy', 20);
function return_policy() {
    $info = get_cfc_field('rp-info-meta', 'rp-info-custom-field');
    echo '<div id="return-policy-wrapper">';
    echo $info;
    echo '</div>';
}

?>

Answer 3

You can't use <?php inside another <?php [...] ?> block.

You code should be similar to that:

<?php
add_action( 'woocommerce_single_product_summary', 'return_policy', 20 );
function return_policy() {
    echo '<div id="return-policy-wrapper">' . the_cfc_field('rp-info-meta', 'rp-info-custom-filed') . '</div>';
}

If you see carefully, HTML content is inside single quotes and never contains other single quoted characters (only double ones). Then, I concat the HTML text with the the_cfc_field() function that returns a string and then concat back with more html.