c#和php文件之间的Json请求

我想将json请求从c#发送到php文件，并将数据保存到文本文件中，但php文件无法读取数据 这是我的密码

User user = new User { id = 1, name = "Bob", address = "password", phone = "0111111111", activation = true };
                string json = "{\"id\":" + "\"" + user.id + "\""
                        + ",\"name\":" + "\"" + user.name + "\""
                        + ",\"address\":" + "\"" + user.address + "\""
                        + ",\"activation\":" + "\"" + user.activation + "\"}";

                HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://localhost:8080/test.php");

                request.Method = "POST";
                request.ContentType = "application/json";
                request.ContentLength = json.Length;

                using (var streamWriter = new StreamWriter(request.GetRequestStream()))
                {
                    streamWriter.Write(json);
                    streamWriter.Close();

                    var httpResponse = (HttpWebResponse)request.GetResponse();
                    using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
                    {
                        var result = streamReader.ReadToEnd();
                    }
                }

和php文件id

<?php
$data = json_decode(file_get_contents('php://input'), true);

$file = "LogFile.txt";
$handle = fopen($file, 'a') or die('ERROR: Cannot write to file: ' . $file);
date_default_timezone_set('Europe/Amsterdam');

fwrite($handle, $data); 
fclose($handle);
echo "SUCCESS";

请问我必须在php文件中做什么才能正确阅读？谢谢
这段代码是我解决自己问题所需要的全部：

$_data = json_decode(file_get_contents('php://input'), true);

if (isset($_data)) {
    $file = "users.txt";
    file_put_contents($file, json_encode($_data));
} 

您的
$data
是否为空。有json错误吗？您认为如何以任何方式将对象写入文件？您将在
LogFile.txt
中只找到
对象
或
数组
。哦，不要使用字符串连接手动生成JSON。@YeldarKurmangaliyev也是正确的，请参阅