如图：
为什么下面这句话没有输出任何东西？
echo json_encode($result);#输出结果
个人觉得可能是因为$data里面的数组元素为Client对象，在转为json的时候出问题了。但是我不知道是什么问题，怎么转换？或者有没有其他的转换方法？
class Result { var $state; var $data = array(); } 完整代码：
$start = 0; $end = 2; $uid = 1; $result = new Result(); $result_set = getClients($start, $end, $uid); $data = array(); $count = 0; while($row = mysql_fetch_array($result_set)) { $client = new Client(); $client->cid = $row['id']; $client->gender = $row['gender']; $client->rank = $row['rank']; $client->name = $row['name']; $client->phoneNum = $row['phoneNum']; $client->email = $row['email']; $client->address = $row['address']; $result->data[$count] = $client; echo $result->data[$count]->cid." "; echo $result->data[$count]->gender." "; echo $result->data[$count]->rank." "; echo $result->data[$count]->name." "; echo $result->data[$count]->phoneNum." "; echo $result->data[$count]->address."\n"; $count++; } if(count($data) > 0) { $result->state = 0; } else { $result->state = 1; } echo json_encode($result);#输出结果 class Result { var $state; var $data = array(); } 输出结果：
---------- debug php ----------Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in D:\WWW\wsd\trunk\src\server\api\db\init_db.php on line 10Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in D:\WWW\wsd\trunk\src\server\api\db\init_db.php on line 103 0 经理 张小莉 18825044888 广东省广州市天河区4 0 主管 吴美凤 18576430777 广东省深圳市南山区蛇口南海大道1079号PHP Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in D:\WWW\wsd\trunk\src\server\api\db\init_db.php on line 10PHP Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in D:\WWW\wsd\trunk\src\server\api\db\init_db.php on line 10Output completed (0 sec consumed) - Normal Termination
应该有输出类似这种格式才对的：
{"state":1,"data":[ {"cid":3, "gender":0, "rank":"经理" "name":" 张小莉" "phoneNum":"18825044888 " "address":"广东省广州市天河区"}, {"cid":4, "gender":0, "rank":"主管" "name":" 吴美凤" "phoneNum":"18576430777 " "address":" 广东省深圳市南山区蛇口南海大道1079号"} ]} 请问这是什么问题呢？怎么解决？谢谢！
回复讨论(解决方案)
print_r($result);
能看到什么？
$result是一个对象来的，输出有错：
Catchable fatal error: Object of class Result could not be converted to string in D:\WWW\wsd\trunk\src\server\api\getClients.php on line 44
Object of class Result could not be converted to string 对象不能被转换为字符串
既如此，当然也不能 json 了
看看你的 Client 类定义
可能没有值吧
编码问题，json_encode()只对utf-8有效，创建数据库表的时候设置好表的编码为utf-8，连接数据库的时候也设置一下编码就行了，类似：
function connect_host() {
$host = "127.0.0.1";
$name_db = "root";
$password_db ="root";
$name_tb = "wsd_db";
$con = mysql_connect($host, $name_db, $password_db);
if(!$con) {
echo "connect host failed". mysql_error();
return;
}
mysql_select_db($name_tb, $con);
mysql_query("SET NAMES UTF8");#设置utf-8编码
return $con;
}