不知是RSS ATOM錯亂還是怎麼的，feedly RSS閱讀器冒出一篇Rick Strahl 2012的老文章 Using JSON.NET for dynamic JSON parsing ，讓我大吃一驚，發現自己一直用JProperty的笨拙方法處理動態JSON物件，其實結合dynamic就能大幅簡化。莫名其妙讀到兩年多前的文章，是老天爺的安排吧？擔心不順從天意會遭天譴，特筆記分享之。XD
以下範例示範使用強型別物件、JObject＋JProperty、JObject＋dymanic三種不同做法，處理JSON反序列化及序列化。
using Newtonsoft.Json;using Newtonsoft.Json.Linq;using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace JsonNetLab{class Program {staticvoid Main(string[] args)
{lab1();
lab2();
lab3();
lab4();
lab5();
lab6();
Console.Read();
}
staticstring jsonSrc =
@"{ ""d"": ""2015-01-01T00:00:00Z"",
""n"": 32767,
""s"": ""darkthread"",
""a"": [ 1,2,3,4,5 ]
}";
publicclass foo
{public DateTime d { get; set; }publicint n { get; set; }
publicstring s { get; set; }
publicint[] a { get; set; }
}
//方法1 定義強型別物件接收資料staticvoid lab1()
{foo f = JsonConvert.DeserializeObject<foo>(jsonSrc);
Console.WriteLine("d:{0},n:{1},s:{2},a:{3}", f.d, f.n, f.s, string.Join("/", f.a));
}
//方法2 使用JObject、JProperty、JArray、JToken物件staticvoid lab2()
{JObject jo = JObject.Parse(jsonSrc);
DateTime d = jo.Property("d").Value.Value<DateTime>();int n = jo["n"].Value<int>();
string s = jo["s"].Value<string>();
int[] ary = jo["a"].Value<JArray>()
.Select(o => o.Value<int>()).ToArray(); Console.WriteLine("d:{0},n:{1},s:{2},a:{3}", d, n, s, string.Join("/", ary));
}
//方法3 使用dynamicstaticvoid lab3()
{JObject jo = JObject.Parse(jsonSrc);
dynamic dyna = jo as dynamic; var ary = ((JArray)jo["a"]).Cast<dynamic>().ToArray(); Console.WriteLine("d:{0},n:{1},s:{2},a:{3}", dyna.d, dyna.n, dyna.s,string.Join("/", ary));
}
//方法1 使用強型別staticvoid lab4()
{ foo f = new foo() { d = new DateTime(2015, 1, 1),n = 32767,
s = "darkthread",a = newint[] { 1, 2, 3, 4, 5 }
};
Console.WriteLine("JSON:{0}", JsonConvert.SerializeObject(f));}
//方法2 使用JObject、JPorperty、JArraystaticvoid lab5()
{ JObject jo = new JObject();jo.Add(new JProperty("d", new DateTime(2015, 1, 1)));
jo.Add(new JProperty("n", 32767));
jo.Add(new JProperty("s", "darkthread"));
jo.Add(new JProperty("a", new JArray(1, 2, 3, 4, 5)));
Console.WriteLine("JSON:{0}", jo.ToString(Formatting.None));}
//方法6 使用dynamicstaticvoid lab6()
{ dynamic dyna = new JObject(); dyna.d = new DateTime(2015, 1, 1);dyna.n = 32767;
dyna.s = "darkthread"; dyna.a = new JArray(1, 2, 3, 4, 5); Console.WriteLine("JSON:{0}", dyna.ToString(Formatting.None));}
}
}
相較之下，使用dynamic動態型別，效果與使用JProperty存取相同，但程式碼簡潔許多，未來在.NET 4+環境就決定用它囉～
