PHP读取mssql json数据中文乱码的解决办法

<?php 
/**
* 如果员工编号在MySql中不存在则在MySql中插入员工记录
* 如果该员工编号已经存在则进行更新操作
*/
//如果用JSON格式则要使用text/html，不能使用text/xml
header("Content-Type: text/html;charset=utf-8");
// header("Content-Type: text/html;charset=GBK");
//告诉浏览器不要缓存数据
header("Cache-Control: no-cache");
require '../conn.php';
$seq = $_POST["seq"];
$employeeID = $_POST["employeeID"];
$employeeName = $_POST["employeeName"];
$department = $_POST["department"];
if(!isset($seq) || $seq == ""){//seq不存在则插入新记录
$query = "INSERT INTO employees (employeeID, employeeName, department, 
createTime, updateTime)
VALUES (N'$employeeID',N'$employeeName',N'$department', 
getdate(), getdate())";
}else{//如果seq已存在则更新已有记录
$query = "UPDATE employees SET employeeID='$employeeID', 
employeeName='$employeeName',department='$department',
updateTime=getdate() 
WHERE seq='$seq'";
}
// file_put_contents("E:/mylog.log", $query."\r\n",FILE_APPEND);//用于调试
<span style="color:#FF0000;">$query = iconv("utf-8", "gbk//ignore", $query);//为了解决中文乱码问题</span>
if($result = sqlsrv_query($conn, $query)){
echo true;
}else{
echo false;
}
// echo $query;
?>