C# 结构体和List<T>类型数据转Json数据保存和读取
一.结构体转Json
public struct FaceLibrary
{
public string face_name;
public byte[] face_Feature;
}
//序列化结构体
facelibrary = new FaceLibrary();
facelibrary.face_name = "zhangsan";
facelibrary.face_Feature = new byte[] { 0xaa, 0x22, 0x36, 0x45, 0xff };
MemoryStream stream1 = new MemoryStream();
DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(FaceLibrary));
ser.WriteObject(stream1, facelibrary);
stream1.Position = ;
StreamReader sr = new StreamReader(stream1);
Console.Write("JSON form of Person object: ");
Console.WriteLine(sr.ReadToEnd());
//打印结果：
JSON form of Person object: [{"face_Feature":[,,,,],"face_name":"zhangsan"}
//反序列化结构体
stream1.Position = ;
FaceLibrary p2 = (FaceLibrary)ser.ReadObject(stream1);
Console.WriteLine(p2.face_name);
Console.WriteLine(p2.face_Feature);
//输出结果：
wangjin01
System.Byte[]
说明： 通过如上操作，能够将结构体的数据转为Json数据
方法二： 将List<T> 结构的数据转为Json数据
public struct FaceLibrary
{
public string face_name;
public byte[] face_Feature;
}
List<FaceLibrary> listfacex = new List<FaceLibrary>();
//序列化List<T>
facelibrary = new FaceLibrary();
facelibrary.face_name = "zhangsan01";
facelibrary.face_Feature = new byte[] { 0xaa, 0x22, 0x36, 0x45, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan02";
facelibrary.face_Feature = new byte[] { 0xaa, 0x22, 0x36, 0x45, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan03";
facelibrary.face_Feature = new byte[] { 0xaa, 0x22, 0x36, 0x45, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan04";
facelibrary.face_Feature = new byte[] { 0xaa, 0x22, 0x36, 0x45, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan05";
facelibrary.face_Feature = new byte[] { 0xaa, 0x22, 0x36, 0x45, 0xff };
listfacex.Add(facelibrary);
MemoryStream stream1 = new MemoryStream();
DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(List<FaceLibrary>));
ser.WriteObject(stream1, listfacex);
stream1.Position = ;
StreamReader sr = new StreamReader(stream1);
Console.Write("JSON form of Person object: ");
Console.WriteLine(sr.ReadToEnd());
//输出结果：
JSON form of Person object: [
{"face_Feature":[,,,,],"face_name":"zhangsan01"},
{"face_Feature":[,,,,],"face_name":"zhangsan02"},
{"face_Feature":[,,,,],"face_name":"zhangsan03"},
{"face_Feature":[,,,,],"face_name":"zhangsan04"},
{"face_Feature":[,,,,],"face_name":"zhangsan05"}
]
//反序列化List<T>
stream1.Position = ;
List<FaceLibrary> p2 = (List<FaceLibrary>)ser.ReadObject(stream1);
Console.WriteLine(p2[].face_name);
Console.WriteLine(p2[].face_Feature);
//输出结果：
zhangsan01
System.Byte[]
三.测试应用
/*
应用需求：
1. 通过List<T>将结构体类型<T>的多个数据加载到List<T>中;
2. 将List<T>数据转为Json数据,并写入到文件中;
3. 从文件中读取保存的Json数据，并还原成List<T>数据供后续调用;
//说明： JavaScriptSerializer 需要导入相应的库，
命名空间: System.Web.Script.Serialization
程序集: System.Web.Extensions（位于 System.Web.Extensions.dll）
参考文件：https://msdn.microsoft.com/zh-cn/library/system.web.script.serialization.javascriptserializer.aspx
*/
//1.定义结构体和List<T>
public struct FaceLibrary
{
public string face_name;
public byte[] face_Feature;
}
FaceLibrary facelibrary;
List<FaceLibrary> listfacex = new List<FaceLibrary>();
//2. 添加数据到List<T>中
facelibrary.face_name = "zhangsan01";
facelibrary.face_Feature = new byte[] { 0xaa, 0x01, 0x11, 0x21, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan02";
facelibrary.face_Feature = new byte[] { 0xaa, 0x02, 0x12, 0x22, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan03";
facelibrary.face_Feature = new byte[] { 0xaa, 0x03, 0x13, 0x23, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan04";
facelibrary.face_Feature = new byte[] { 0xaa, 0x04, 0x14, 0x24, 0xff };
listfacex.Add(facelibrary);
facelibrary.face_name = "zhangsan05";
facelibrary.face_Feature = new byte[] { 0xaa, 0x05, 0x15, 0x25, 0xff };
listfacex.Add(facelibrary);
//3. 将List<T>数据转为Json数据
String str = JsonListToString(listfacex);
//JSON序列化,将List<T>转换为String
private String JsonListToString (List<FaceLibrary> list)
{
JavaScriptSerializer Serializerx = new JavaScriptSerializer();
string changestr = Serializerx.Serialize(list);
return changestr;
}
//4. 将Json数据写入文件系统
FileWrite("test.txt",str)
//写入文件
private void FileWrite(string filepath,string writestr)
{
FileStream fs = new FileStream(filepath, FileMode.OpenOrCreate);
StreamWriter sw = new StreamWriter(fs);
sw.Write(writestr);
sw.Close();
fs.Close();
}
//5. 从文件中读取Json数据
string str = FileRead("test.txt");
//读取文件
private string FileRead(string filepath)
{
FileStream fs = new FileStream(filepath, FileMode.Open);
StreamReader sr = new StreamReader(fs);
string str = sr.ReadToEnd();
sr.Close();
fs.Close();
return str;
}
//6. 将Json数据转换为List<T>数据
List<FaceLibrary> listface = StringToJsonList(str)；
//JSON反序列化,将List<T>转换为String
private List<FaceLibrary> StringToJsonList(string str)
{
JavaScriptSerializer Serializer = new JavaScriptSerializer();
List<FaceLibrary> face = Serializer.Deserialize<List<FaceLibrary>>(str);
return face;
}
//以上方法基本能够解决上述问题；
以上代码基于参考如下代码，
/*
// C#将Json字符串反序列化成List对象类集合
using System.IO;
using System.Web.Script.Serialization;
using System.Runtime.Serialization.Json;
public static List<T> JSONStringToList<T>(this string JsonStr)
{
JavaScriptSerializer Serializer = new JavaScriptSerializer();
List<T> objs = Serializer.Deserialize<List<T>>(JsonStr);
return objs;
}
public static T Deserialize<T>(string json)
{
T obj = Activator.CreateInstance<T>();
using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(json)))
{
DataContractJsonSerializer serializer = new DataContractJsonSerializer(obj.GetType());
return (T)serializer.ReadObject(ms);
}
}
//好了，我们来测试下
string JsonStr = "[{Name:'苹果',Price:5.5},{Name:'橘子',Price:2.5},{Name:'柿子',Price:16}]";
List<Product> products = new List<Product>();
products = JSONStringToList<Product>(JsonStr);
//Response.Write(products.Count());
foreach (var item in products)
{
Response.Write(item.Name + ":" + item.Price + "<br />");
}
public class Product
{
public string Name { get; set; }
public double Price { get; set; }
}
结果：
苹果:5.5
橘子:2.5
柿子:16
*/