使用System.Text.Json设置JsonSerializerOptions。writeindent = true:

JsonSerializerOptions options = new JsonSerializerOptions { WriteIndented = true };
string json = JsonSerializer.Serialize<Type>(object, options);

如果你有一个JSON字符串，想要“美化”它，但不想将它序列化到一个已知的c#类型，那么下面的方法就可以了(使用JSON.NET):

using System;
using System.IO;
using Newtonsoft.Json;

class JsonUtil
{
    public static string JsonPrettify(string json)
    {
        using (var stringReader = new StringReader(json))
        using (var stringWriter = new StringWriter())
        {
            var jsonReader = new JsonTextReader(stringReader);
            var jsonWriter = new JsonTextWriter(stringWriter) { Formatting = Formatting.Indented };
            jsonWriter.WriteToken(jsonReader);
            return stringWriter.ToString();
        }
    }
}

Json的简短示例代码。网络图书馆

private static string FormatJson(string json)
{
    dynamic parsedJson = JsonConvert.DeserializeObject(json);
    return JsonConvert.SerializeObject(parsedJson, Formatting.Indented);
}

修饰现有JSON的最短版本:(编辑:使用JSON.net)

JToken.Parse("mystring").ToString()

输入:

{"menu": { "id": "file", "value": "File", "popup": { "menuitem": [ {"value": "New", "onclick": "CreateNewDoc()"}, {"value": "Open", "onclick": "OpenDoc()"}, {"value": "Close", "onclick": "CloseDoc()"} ] } }}

输出:

{
  "menu": {
    "id": "file",
    "value": "File",
    "popup": {
      "menuitem": [
        {
          "value": "New",
          "onclick": "CreateNewDoc()"
        },
        {
          "value": "Open",
          "onclick": "OpenDoc()"
        },
        {
          "value": "Close",
          "onclick": "CloseDoc()"
        }
      ]
    }
  }
}

漂亮地打印一个对象:

JToken.FromObject(myObject).ToString()

2023年更新

对于那些问我如何使用c#在。net中获得格式化JSON并想要看到如何立即使用它的人和一行爱好者。以下是缩进的JSON字符串一行代码:

有两种知名的JSON格式化器或解析器可以序列化:

Newtonsoft Json。网版:

using Newtonsoft.Json;

var jsonString = JsonConvert.SerializeObject(yourObj, Formatting.Indented);

.Net 7版本:

using System.Text.Json;

var jsonString = JsonSerializer.Serialize(yourObj, new JsonSerializerOptions { WriteIndented = true });

你可以使用以下标准方法来获取格式化的Json

JsonReaderWriterFactory。CreateJsonWriter(流流，编码编码，bool ownsStream, bool缩进，字符串indentChars)

只设置"缩进==true"

试试这样的方法

    public readonly DataContractJsonSerializerSettings Settings = 
            new DataContractJsonSerializerSettings
            { UseSimpleDictionaryFormat = true };

    public void Keep<TValue>(TValue item, string path)
    {
        try
        {
            using (var stream = File.Open(path, FileMode.Create))
            {
                //var currentCulture = Thread.CurrentThread.CurrentCulture;
                //Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;

                try
                {
                    using (var writer = JsonReaderWriterFactory.CreateJsonWriter(
                        stream, Encoding.UTF8, true, true, "  "))
                    {
                        var serializer = new DataContractJsonSerializer(type, Settings);
                        serializer.WriteObject(writer, item);
                        writer.Flush();
                    }
                }
                catch (Exception exception)
                {
                    Debug.WriteLine(exception.ToString());
                }
                finally
                {
                    //Thread.CurrentThread.CurrentCulture = currentCulture;
                }
            }
        }
        catch (Exception exception)
        {
            Debug.WriteLine(exception.ToString());
        }
    }

注意线条

    var currentCulture = Thread.CurrentThread.CurrentCulture;
    Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
    ....
    Thread.CurrentThread.CurrentCulture = currentCulture;

对于某些类型的xml序列化器，您应该使用InvariantCulture来避免在具有不同区域设置的计算机上反序列化期间出现异常。例如，double或DateTime的无效格式有时会导致错误。

在反序列化

    public TValue Revive<TValue>(string path, params object[] constructorArgs)
    {
        try
        {
            using (var stream = File.OpenRead(path))
            {
                //var currentCulture = Thread.CurrentThread.CurrentCulture;
                //Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;

                try
                {
                    var serializer = new DataContractJsonSerializer(type, Settings);
                    var item = (TValue) serializer.ReadObject(stream);
                    if (Equals(item, null)) throw new Exception();
                    return item;
                }
                catch (Exception exception)
                {
                    Debug.WriteLine(exception.ToString());
                    return (TValue) Activator.CreateInstance(type, constructorArgs);
                }
                finally
                {
                    //Thread.CurrentThread.CurrentCulture = currentCulture;
                }
            }
        }
        catch
        {
            return (TValue) Activator.CreateInstance(typeof (TValue), constructorArgs);
        }
    }

谢谢!