如何反序列化我的 jSON 字符串数组以获取我的用户名？

Question

正如您在我的 PHP 脚本中看到的那样，我编写了一个查询，通过使用唯一 ID 从特定用户（登录时）获取所有用户数据。当我得到 JSON 字符串时，我只需要用户名。我想在我的模拟器屏幕上显示的用户名：

PHP-code（不用担心SQL注入-->我稍后会修复它）

<?php

$db = new mysqli('localhost', 'root', '', 'test');

$Id = mysqli_real_escape_string($db, $_POST['Id']);

$res = mysqli_query($db, "SELECT * from User WHERE Id = '$Id'");

$rows = array();

while($r = mysqli_fetch_assoc($res)) 
{
    $rows[] = $r;
}

echo json_encode($rows);

?>

Xamarin 代码 所以我只想反序列化 json 字符串的用户名，然后将其显示在模拟器屏幕上。有人可以帮我反序列化用户名对象吗？在此代码中，'List' 和 'res' 带有红色下划线...

    public async void GetUserData()
    {
        user u = new user();

        HttpResponseMessage res;

        var content = new FormUrlEncodedContent(new[]
        {
            new KeyValuePair<string, string>("Id", u.Id)
        });

        res = await client.PostAsync("http://10.0.2.2/DATA/USER/DataByID/Data.php", content);

        var user = JsonConvert.DeserializeObject<List>(res); // 'res' and '<List>' are underlined

        u.Username = users[1]; // I want to refer to the second property in the json string (Username)

        BindingContext = u; // displaying the Username on the screen of the emulator
    }

JSON - 字符串

[{"Id":"13","Username":"aze","Email":"aze@aze.be","Passwd":"0a5b3913cbc9a9092311630e869b4442","Age":"27"}]

Answer 1

var json = await result.Content.ReadAsStringAsync();
var users = JsonConvert.DeserializeObject<List<user>>(json);
u = users[0];
// u will now contain all of your user properties
BindingContext = u;

如何反序列化我的 jSON 字符串数组以获取我的用户名？

How to deserialize my jSON string array to obtain my Username?

php

json

json-deserialization

xamarin.forms