C#中字典Dictionary与自定义类型CustomType之间的转换
思路：
可以使用反射System.Reflection来获取类的具体属性，
属性名称就映射字典的键Key。
新建控制台程序DictionaryCustomClassConversionDemo
第一步、新建关键转换类ConversionUtil。
类ConversionUtil的源代码如下：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
namespace DictionaryCustomClassConversionDemo
{
/// <summary>
/// 字典Dictionary与自定义类CustomClass属性之间的转化
/// 斯内科 2024-05-10
/// </summary>
public class ConversionUtil
{
/// <summary>
/// 将一个实体类的属性转化为键值对集合，键为属性名PropertyName，值为对应的值
/// </summary>
/// <typeparam name="T">一种自定义类，该类必须已实例化</typeparam>
/// <param name="obj">实例化后的类对象</param>
/// <returns>返回转化后的字典</returns>
public static Dictionary<string, object> CustomClassToDictionary<T>(T obj) where T : class, new()
{
Dictionary<string, object> dict = new Dictionary<string, object>();
Type type = typeof(T);
PropertyInfo[] propertyInfos = type.GetProperties();
for (int i = 0; i < propertyInfos.Length; i++)
{
string key = propertyInfos[i].Name;
object val = propertyInfos[i].GetValue(obj);
dict.Add(key, val);
}
return dict;
}
/// <summary>
/// 将字典转化为实例化类，如果类的属性名称在字典中存在该键key，就使用该键对应的值为类的属性key赋值【注意，转化可能因值的类型、范围等不同而导致失败】
/// 如果类的属性名称在字典中不存在该键key，则不进行赋值，只是按属性对应类型的默认值处理
/// </summary>
/// <typeparam name="T">要转化的目标类型</typeparam>
/// <param name="dict">键值对字典</param>
/// <returns>要获取的目标实例化类对象，如果字典为空，则按类的默认值处理</returns>
public static T DictionaryToCustomClass<T>(Dictionary<string, object> dict) where T : class
{
T obj = default(T);
if (dict == null || dict.Count == 0)
{
return obj;
}
Type type = typeof(T);
obj = (T)Activator.CreateInstance(type);
PropertyInfo[] propertyInfos = type.GetProperties();
for (int i = 0; i < propertyInfos.Length; i++)
{
string key = propertyInfos[i].Name;
if (dict.ContainsKey(key))
{
propertyInfos[i].SetValue(obj, dict[key]);
}
}
return obj;
}
}
}
二、新建实体测试类TestClass。
测试类TestClass源程序如下：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace DictionaryCustomClassConversionDemo
{
/// <summary>
/// 测试类
/// </summary>
public class TestClass
{
/// <summary>
/// 主键
/// </summary>
public int CoreID { get; set; }
/// <summary>
/// 档位编号
/// </summary>
public int LevelId { get; set; }
/// <summary>
/// 电压下限
/// </summary>
public double VoltageMin { get; set; }
/// <summary>
/// 电压上限
/// </summary>
public double VoltageMax { get; set; }
/// <summary>
/// 内阻值
/// </summary>
public string Resistance { get; set; }
/// <summary>
/// 修改时间
/// </summary>
public DateTime ModifyTime { get; set; }
public override string ToString()
{
return $"{{CoreID:{CoreID},\nLevelId:{LevelId},\nVoltageMin:{VoltageMin},\nVoltageMax:{VoltageMax},\nResistance:{Resistance},\nModifyTime:{ModifyTime.ToString("yyyy-MM-dd HH:mm:ss")}}}";
}
}
}
三、调用测试Program如下：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace DictionaryCustomClassConversionDemo
{
class Program
{
static void Main(string[] args)
{
Console.SetWindowSize(100, 60);
try
{
TestClass testClass = new TestClass()
{
CoreID = 6,
LevelId = 3,
VoltageMin = 3.10,
VoltageMax = 3.99,
Resistance = "888MΩ",
ModifyTime = DateTime.Now
};
Console.WriteLine($"--------打印原对象信息:--------");
Console.WriteLine(testClass);
Dictionary<string, object> dict = ConversionUtil.CustomClassToDictionary(testClass);
Console.WriteLine("--------打印类对象转化后的字典信息:--------");
for (int i = 0; i < dict.Count; i++)
{
KeyValuePair<string, object> keyValuePair = dict.ElementAt(i);
Console.WriteLine($"{keyValuePair.Key}:{keyValuePair.Value}");
}
Console.WriteLine();
Console.WriteLine("--------测试字典转化为类--------");
dict["Resistance"] = "333MΩ";
dict["LevelId"] = 1;
dict["VoltageMax"] = 5;
dict.Add("额外参数", "额外值");
Console.WriteLine("--------打印原字典信息1:--------");
for (int i = 0; i < dict.Count; i++)
{
KeyValuePair<string, object> keyValuePair = dict.ElementAt(i);
Console.WriteLine($"{keyValuePair.Key}:{keyValuePair.Value}");
}
TestClass testObj1 = ConversionUtil.DictionaryToCustomClass<TestClass>(dict);
Console.WriteLine("--------打印字典转化为类对象1--------");
Console.WriteLine(testObj1);
Console.WriteLine();
dict["Resistance"] = 66666;
dict["LevelId"] = 5;
Console.WriteLine("--------打印原字典信息2:--------");
for (int i = 0; i < dict.Count; i++)
{
KeyValuePair<string, object> keyValuePair = dict.ElementAt(i);
Console.WriteLine($"{keyValuePair.Key}:{keyValuePair.Value}");
}
TestClass testObj2 = ConversionUtil.DictionaryToCustomClass<TestClass>(dict);
Console.WriteLine("--------打印字典转化为类对象2--------");
Console.WriteLine(testObj2);
}
catch (Exception ex)
{
Console.WriteLine($"{ex.Message}.异常类型【{ex.GetType()}】");
}
Console.ReadLine();
}
}
}
4、程序运行如图：
