php中json_encode gbk/gb2312中文乱码

$arr = array ( 

  array ( 

      'catid' => '4', 

      'catname' => 'www.111cn.net', 

      'meta_title' => '一聚教程网2' 

    )
);
 
echo json_encode($arr);

结果

[{"catid":"4","catname":"www.111cn.net","meta_title":null}]

$testJSON=array(‘name’=>’中文字符串’,’value’=>’test’);
//echo json_encode($testJSON);
foreach ( $testJSON as $key => $value ) {
$testJSON[$key] = urlencode ( $value );
}
echo urldecode ( json_encode ( $testJSON ) );
?>

查看输出结果为：

{“name”:”中文字符串”,”value”:”test”}