我通过插入acf/pre_save_post. 使用它，您可以测试$\\u POST数据。如果您不喜欢某些内容，可以在返回时将$post\\u id更改为“error”。这将阻止处理表单，因为post\\u id不正确。您还可以插入到acf/save_post 确保从表单中取消设置“返回”或更新消息。

这一切都有点复杂，但我将尝试给出一个我使用的简化示例。

$submitted_fields = \'\';
$validation_errors = \'\';

add_filter( \'acf/pre_save_post\', \'custom_validation\' );
function custom_validation( $post_id )
{
    // Load the fields from $_POST
    if ( empty($_POST[\'fields\']) || ! is_array($_POST[\'fields\']) )
    {
        $validation_errors[\'empty\'] = "One or more fields below are required";
    }
    else
    {
        foreach( $_POST[\'fields\'] as $k => $v )
        {
            // get field
            $f = apply_filters(\'acf/load_field\', false, $k );
            $f[\'value\'] = $v;
            $submitted_fields[$f[\'name\']] = $f;
        }
    }

    // Test stuff...
    if ( empty($submitted_fields[\'foo\']) || \'bar\' != $submitted_fields[\'foo\'] )
    {
        $validation_errors[\'foo\'] = "Foo did not equal bar";
    }

    // If there are errors, output them, keep the form from processing, and remove any redirect
    if ( $validation_errors )
    {
        // Output the messges area on the form
        add_filter( \'acf/get_post_id\', array(__CLASS__, \'add_error\') );
        // Turn the post_id into an error
        $post_id = \'error\';
        // Add submitted values to fields
        add_action(\'acf/create_fields\', array(__CLASS__, \'acf_create_fields\'), 10, 2 );
    }
    else
    {
        // Do something... do nothing... ?
    }

    // return the new ID
    return $post_id;
}

    function acf_create_fields( $fields, $post_id )
    {
        foreach ( $fields as &$field )
        {
            if ( array_key_exists($field[\'name\'], $submitted_fields) )
                $field[\'value\'] = $submitted_fields[$field[\'name\']];
        }
        return $fields;
    }

    function add_error()
    {
        echo \'<div id="message" class="error">\';
        foreach ( $validation_errors as $key => $error )
        {
            echo \'<p class="\' . $key . \'">\' . $error . \'</p>\';
        }
        echo \'</div>\';
    }

add_action(\'acf/save_post\', \'custom_handle_error\', 1);
function custom_handle_error( $post_id )
{
    if ( \'error\' == $post_id )
    {
        unset($_POST[\'return\']);
    }
}

从5.0版开始，您可以使用acf/validate_value 过滤器-请参阅official documentation.

您可以使用此代码

add_filter(\'acf/validate_value/name=validate_this_image\', \'my_acf_validate_value\', 10, 4);

function my_acf_validate_value( $valid, $value, $field, $input ){

// bail early if value is already invalid
if( !$valid ) {

    return $valid;

}


// load image data
$data = wp_get_attachment_image_src( $value, \'full\' );
$width = $data[1];
$height = $data[2];

if( $width < 960 ) {

    $valid = \'Image must be at least 960px wide\';

}


// return
return $valid;


}