服务器返回中文乱码有关问题

服务器返回中文乱码问题
服务器端是用php写的，直接显示在浏览器中文是乱码，android接收中文也是乱码，数据库编码，数据库表，字段，数据库连接，apache服务器编码都是utf-8，

这是在浏览器看到的结果：content字段在数据库中是中文
{"posts":[{"post":{"ID":"1","Account_ID":"A220","Receiver_ID":"B220","Consumption_Amount":"100","Content":"\u9910\u5385\u6d88\u8d39","Time":"2013-08-20"}},{"post":{"ID":"3","Account_ID":"A220","Receiver_ID":"B221","Consumption_Amount":"10","Content":"\u516c\u4ea4\u8f66\u6d88\u8d39","Time":"2013-08-21"}},{"post":{"ID":"4","Account_ID":"A220","Receiver_ID":"B222","Consumption_Amount":"500","Content":"\u8d2d\u7269\u6d88\u8d39","Time":"2013-08-22"}},{"post":{"ID":"5","Account_ID":"A220","Receiver_ID":"B223","Consumption_Amount":"50","Content":"\u516c\u4ea4\u8f66\u6d88\u8d39","Time":"2013-08-08"}},{"post":{"ID":"6","Account_ID":"A220","Receiver_ID":"B224","Consumption_Amount":"100","Content":"\u624b\u673a\u5145\u503c","Time":"2013-08-10"}},{"post":{"ID":"7","Account_ID":"A220","Receiver_ID":"B225","Consumption_Amount":"1000","Content":"\u8f6c\u8d26","Time":"2013-08-06"}}]}
服务器端代码：

  header("Content-Type: text/html; charset=UTF-8"); 

  $format = 'json'; //xml is the default  

  /* 连接数据库*/  

  $link = mysql_connect('localhost','root','199209') or die('Cannot connect to the DB');

 // mysql_query("SET NAMES UTF8");  

  mysql_select_db('citi_db',$link) or die('Cannot select the DB');  

  mysql_query("SET NAMES utf8");

  mysql_query("SET CHARACTER_SET_CLIENT=utf8");

  mysql_query("SET CHARACTER_SET_RESULTS=utf8"); 

  $query = "SELECT *  FROM `consumption_detail` WHERE `Account_ID` = 'A220'";  

  $result = mysql_query($query,$link) or die('Errant query:  '.$query);  

  

  $posts = array();  

  if(mysql_num_rows($result)) {  

    while($post = mysql_fetch_assoc($result)) {  

      $posts[] = array('post'=>$post);  

    }  

  }  

  

  /* json格式*/  

  if($format == 'json') {  

    header("Content-type: text/html;charset=UTF-8");  

    echo json_encode(array('posts'=>$posts));  



  }