Encoding - I use PHP to extract data from mysql and then convert it to Json, but why is a question mark displayed in Chinese?

The above is the data in my data inventory, using utf8_bin encoding. At the beginning, I used utf8_unicode_ci, but it still didn’t work.
The following is my PHP code

<code><?php

header('Content-Type:application/json;charset=utf-8');

//定义常量参数
define('DB_HOST','localhost');
define('DB_USER','root');
define('DB_PWD','root');//密码
define('DB_NAME','Test');

$connect = mysql_connect(
   DB_HOST, 
   DB_USER, 
   DB_PWD
)or die('数据库连接失败:'.mysql_error());

mysql_select_db(DB_NAME,$connect) or die('数据库连接错误，错误信息：'.mysql_error());

//从数据库里把表的数据提出来（获取记录集）

$query = "SELECT * FROM gc_DataBase";
$result = mysql_query($query) or die('SQL错误，错误信息：'.mysql_error());

class User {
    public $id ;
    public $name ;
    public $address;
    public $phonenumber;
}
$data =array();
while ($row= mysql_fetch_array($result, MYSQL_ASSOC)){
    $user = new User();
    $user -> id = $row["id"];
    $user -> name = $row["name"];
    $user -> address = $row["address"];
    $user -> phonenumber = $row["phonenumber"];
    $data[] = $user;
}

if (function_exists('mysql_set_charset') === false) {
    mysql_query("SET NAMES UTF8",$data);
}else{
    mysql_set_charset('utf8',$data);
}

$response = array(
    'code'    => 200, 
    'message' => 'success for request',
    'data'    => $data,
);

echo urldecode(json_encode($response));

mysql_free_result($response);  //释放

mysql_close();//关闭数据库
?>

</code>

The last thing displayed in the browser is this urine

<code>{
    "code": 200, 
    "message": "success for request", 
    "data": [
        {
            "id": "100", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13212340001"
        }, 
        {
            "id": "101", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340002"
        }, 
        {
            "id": "100", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13212340001"
        }, 
        {
            "id": "101", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340002"
        }, 
        {
            "id": "0", 
            "name": "", 
            "address": "", 
            "phonenumber": "0"
        }, 
        {
            "id": "103", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340005"
        }, 
        {
            "id": "103", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340005"
        }
    ]
}
</code>

Why is the question mark displayed in Chinese? I just want the Unicode encoding

Reply content:

The above is the data in my data inventory, using utf8_bin encoding. At the beginning, I used utf8_unicode_ci, but it still didn’t work.
The following is my PHP code

<code><?php

header('Content-Type:application/json;charset=utf-8');

//定义常量参数
define('DB_HOST','localhost');
define('DB_USER','root');
define('DB_PWD','root');//密码
define('DB_NAME','Test');

$connect = mysql_connect(
   DB_HOST, 
   DB_USER, 
   DB_PWD
)or die('数据库连接失败:'.mysql_error());

mysql_select_db(DB_NAME,$connect) or die('数据库连接错误，错误信息：'.mysql_error());

//从数据库里把表的数据提出来（获取记录集）

$query = "SELECT * FROM gc_DataBase";
$result = mysql_query($query) or die('SQL错误，错误信息：'.mysql_error());

class User {
    public $id ;
    public $name ;
    public $address;
    public $phonenumber;
}
$data =array();
while ($row= mysql_fetch_array($result, MYSQL_ASSOC)){
    $user = new User();
    $user -> id = $row["id"];
    $user -> name = $row["name"];
    $user -> address = $row["address"];
    $user -> phonenumber = $row["phonenumber"];
    $data[] = $user;
}

if (function_exists('mysql_set_charset') === false) {
    mysql_query("SET NAMES UTF8",$data);
}else{
    mysql_set_charset('utf8',$data);
}

$response = array(
    'code'    => 200, 
    'message' => 'success for request',
    'data'    => $data,
);

echo urldecode(json_encode($response));

mysql_free_result($response);  //释放

mysql_close();//关闭数据库
?>

</code>

The last thing displayed in the browser is this urine

<code>{
    "code": 200, 
    "message": "success for request", 
    "data": [
        {
            "id": "100", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13212340001"
        }, 
        {
            "id": "101", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340002"
        }, 
        {
            "id": "100", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13212340001"
        }, 
        {
            "id": "101", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340002"
        }, 
        {
            "id": "0", 
            "name": "", 
            "address": "", 
            "phonenumber": "0"
        }, 
        {
            "id": "103", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340005"
        }, 
        {
            "id": "103", 
            "name": "??", 
            "address": "????", 
            "phonenumber": "13512340005"
        }
    ]
}
</code>

Why is the question mark displayed in Chinese? I just want the Unicode encoding

<code>if (function_exists('mysql_set_charset') === false) {
    mysql_query("SET NAMES UTF8",$data);
}else{
    mysql_set_charset('utf8',$data);
}</code>

This paragraph should be placed before mysql_query. In addition, the second parameter in these two places should not be $data, but should be $connect

I have encountered this problem before, and it was fine after adding this mysqli_query($conn,"SET NAMES utf8");

<code>class DBHelper{
    
    public function DBHelper(){}
    
    private static function getConn(){
        $conn = mysqli_connect(DB_HOST,DB_USER,DB_PWD,DB_NAME);
        mysqli_query($conn,"SET NAMES utf8");
        return $conn;
    }
    
    public static function opearting($sql){
        return mysqli_query(self::getConn(),$sql);
        
    }
}</code>

Chinese urlencode This encoding problem I encountered cannot be decoded directly. Otherwise, garbled characters will appear. The way I use it is.
Individually encoded. Then decoding, ` /**

<code> * [ReturnUrlencode 用递归的方式来遍历所有的数组并且解析]
 * @param [type] $arr [description]
 */
function ReturnUrlencode($arr){
    foreach ($arr as $key => $value){
        if(is_array($value)){   
            $arr[$key]=ReturnUrlencode($value);
        }else{
            $arr[$key]=urlencode($value);
        }
    }
    return $arr;
}`

##这种方式，输出来的json 中文就不会乱码了。
urldecode(json_encode(ReturnUrlencode($arr)));</code>

if (function_exists('mysql_set_charset') === false) {
    mysql_query("SET NAMES UTF8",$data);
}else{
    mysql_set_charset('utf8',$data);
}

This sentence should be placed before traversing the data