感谢您的帮助Sally，这是完整的jQuery，它将RGB值推送到另一个字段。RGB字段的名称_rgb 在最后。

jQuery(function() {
    var myOptions = {
        // you can declare a default color here,
        // or in the data-default-color attribute on the input
        defaultColor: false,
        // a callback to fire whenever the color changes to a valid color
        change: function(event, ui){
            var rgb = ui.color.toCSS( \'rgb\' );
            var name = jQuery(this).attr("name");
            name = \'#\' + name + \'_rgb\';
            jQuery(name).val(rgb);
        },
        // a callback to fire when the input is emptied or an invalid color
        clear: function() {},
        // hide the color picker controls on load
        hide: true,
        // show a group of common colors beneath the square
        // or, supply an array of colors to customize further
        palettes: true
    };
    jQuery(\'.color-field-custom\').wpColorPicker(myOptions);
});

<input type="text" name="destination_secondary_color_rgb" id="destination_secondary_color_rgb" value="<?php echo get_post_meta($post->ID, \'destination_secondary_color_rgb\', true); ?>" />