php - Wordpress 警告 : call_user_func_array() expects parameter 1 to be a valid callback, 数组必须恰好有两个成员

Question

我正在尝试添加一个自定义函数，该函数将添加 Access-Control-Allow-Origin header ，因为我无法访问服务器上的 .conf 文件。

下面是我的代码；

add_filter( 'wp_headers', array( 'eg_send_cors_headers' ), 10, 1 );

function eg_send_cors_headers( $headers ) {

    $headers['Access-Control-Allow-Origin']      = get_http_origin();
    $headers['Access-Control-Allow-Credentials'] = 'true';

    if ( 'OPTIONS' == $_SERVER['REQUEST_METHOD'] ) {
        if ( isset( $_SERVER['HTTP_ACCESS_CONTROL_REQUEST_METHOD'] ) ) {
                $headers['Access-Control-Allow-Methods'] = 'GET, POST, OPTIONS';
        }

        if ( isset( $_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS'] ) ) {
            $headers['Access-Control-Allow-Headers'] = $_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS'];
        }
    }

    return $headers;
}

保存时出现此错误:

Notice: Undefined offset: 1 in /example/wp-includes/plugin.php on line 873 Warning: call_user_func_array() expects parameter 1 to be a valid callback, array must have exactly two members in /example/wp-includes/plugin.php on line 192

Answer 1

因为我只调用一个没有方法的函数，所以我只是在 add_filter 函数中删除了函数名周围的数组 ()。正如您在示例 #1 here 中所见，如果您只调用带参数的函数，则只需将函数名称用单引号引起来。

固定代码如下:

add_filter( 'wp_headers', 'eg_send_cors_headers', 10, 1 );
function eg_send_cors_headers( $headers ) {

        $headers['Access-Control-Allow-Origin']= get_http_origin(); 
        $headers['Access-Control-Allow-Credentials'] = 'true';


        if ( 'OPTIONS' == $_SERVER['REQUEST_METHOD'] ) {

            if ( isset( $_SERVER['HTTP_ACCESS_CONTROL_REQUEST_METHOD'] ) ) {
                $headers['Access-Control-Allow-Methods'] = 'GET, POST, OPTIONS';
            }

            if ( isset( $_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS'] ) ) {
                $headers['Access-Control-Allow-Headers'] = $_SERVER['HTTP_ACCESS_CONTROL_REQUEST_HEADERS'];
            }

        }

    return $headers;
}