阅读Json序列化的C# [英] Read Json Serialized c#

问题描述

我正在尝试从此json文本获取ID.我不确定如何获取它不会让我创建一个json对象.我尝试这样做反序列化:

I am trying to get the id from this json text. I'm not sure how to go about getting it doesn't let me create a json object. I tried deserializing it doing this:

public async Task<List<T>> GetIdAsync(string username)
{
    var httpClient = new HttpClient();

    var json = await httpClient.GetStringAsync(WebServiceURL);

    var  Id  = JsonConvert.DeserializeObject<List<T>>(json);

   return Id;
}

但是在反序列化过程中出现此错误

but I get this error during the deserialization

未处理的异常:

Unhandled Exception:

Newtonsoft.Json.JsonReaderException:遇到意外字符 而解析值:{.路径"，第1行，位置2

Newtonsoft.Json.JsonReaderException: Unexpected character encountered while parsing value: {. Path '', line 1, position 2

这是json文本:

json    "[{\"Id\":1,\"FirstName\":\"a\",\"LastName\":\"b\",\"UserName\":\"user\",\"Email\":\"[e-mail]\",\"Password\":\"poSsUrscOuXL+E5qxXsCsA==\",\"CompanyName\":\"c\",\"Salt\":\"n3ZLSwU9L1g=\",\"Address\":{\"Country\":\"c\",\"Province\":\"p\",\"City\":\"c\",\"PostalCode\":\"p\",\"Street\":\"street\",\"StreetNumber\":\"123\"},\"Telephone\":{\"PersonalPhoneNumber\":\"413414\",\"BusinessPhoneNumber\":\"134134\"},\"Location\":{\"Lat\":45.6025839,\"Lng\":-97.8489959}}]"   string

推荐答案

提供作为对象数组的JSON值.您可以使用动态对象仅提取所需的属性.首先将json反序列化为List<dynamic>，获取列表中的第一个对象，然后调用Id属性.

Given value of provided JSON which is an array of objects. You can use dynamic object to extract just the property you want. First deserialize the json to a List<dynamic>, get the first object in the list and call the Id property.

public async Task<int> GetIdAsync(string username) {
    var httpClient = new HttpClient();

    var json = await httpClient.GetStringAsync(WebServiceURL);

    var list  = JsonConvert.DeserializeObject<List<dynamic>>(json);

    var obj = list.FirstOrDefault();

    int Id = obj != null ? obj.Id : 0;

    return Id;
}

更新:

在一个简单的单元测试中对其进行了测试，并通过了预期的测试.

Tested it in a simple unit test and passes as expected.

[TestClass]
public class UnitTest6 {
    [TestMethod]
    public async Task GetIdAsyncTest() {

        var id = await GetIdAsync("");

        Assert.IsTrue(id > o);
    }

    public async Task<int> GetIdAsync(string username) {
        var httpClient = new HttpClient();
        //simple data just for the purpose of the test.
        var json = await Task.FromResult("[{\"Id\":1,\"FirstName\":\"a\"}]"); //await httpClient.GetStringAsync("");

        var list = JsonConvert.DeserializeObject<List<dynamic>>(json);

        var obj = list.FirstOrDefault();

        int Id = obj != null ? obj.Id : 0;

        return Id;
    }
}

这篇关于阅读Json序列化的C#的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！