(精华)2020年8月9日 C#基础知识点 反射
原理图
/// genericClass = new GenericClass()
Type type1 = type.MakeGenericType(new Type[] { typeof(int), typeof(string), typeof(DateTime) });
object oGenericTest = Activator.CreateInstance(type1);
MethodInfo genericMethod = type1.GetMethod("Show");
genericMethod.Invoke(oGenericTest, new object[] { 123, "零零", DateTime.Now });
}
{
//-----------------反射破坏单利 其实就是反射调用私有构造函数-------------------
Singleton singleton = new Singleton();
Singleton singleton1 = Singleton.GetInstance();
Singleton singleton2 = Singleton.GetInstance();
Singleton singleton3 = Singleton.GetInstance();
Singleton singleton4 = Singleton.GetInstance();
Console.WriteLine(singleton1.Equals(singleton4));
Assembly assembly = Assembly.Load("DB.SqlServer");
Type type = assembly.GetType("DB.SqlServer.Singleton");
object oSingleton1 = Activator.CreateInstance(type, true); //完全等价于 New Singleton
object oSingleton2 = Activator.CreateInstance(type, true);
object oSingleton3 = Activator.CreateInstance(type, true);
object oSingleton4 = Activator.CreateInstance(type, true);
Console.WriteLine(oSingleton1.Equals(oSingleton4));
}
{
//-----------------------反射使用属性字段----------------
People people = new People();
people.Id = 123;
people.Name = "零零";
people.Description = "啦啦啦";
Console.WriteLine($"people.Id={people.Id}");
Console.WriteLine($"people.Name={people.Name}");
Console.WriteLine($"people.Description={people.Description}");
// 1、GetValue其实是有意义的
// 2、SetValue 好像没啥用
Type type = typeof(People);
object oPeople = Activator.CreateInstance(type);
foreach (PropertyInfo prop in type.GetProperties())
{
if (prop.Name.Equals("Id"))
{
prop.SetValue(oPeople, 123);
}
else if (prop.Name.Equals("Name"))
{
prop.SetValue(oPeople, "零零");
}
Console.WriteLine($"oPeople.{prop.Name}={prop.GetValue(oPeople)}");
}
foreach (FieldInfo field in type.GetFields())
{
if (field.Name.Equals("Description"))
{
field.SetValue(oPeople, "啦啦啦");
}
}
}
#endregion
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Console.Read();
}
}
public class SimlpFactory
{
private static string IDBHelperConfig = ConfigurationManager.AppSettings["IDBHelperConfig"];
private static string DllName = IDBHelperConfig.Split(',')[1];
private static string TypeName = IDBHelperConfig.Split(',')[0];
public static IDBHelper CreateInstentce()
{
Assembly assembly = Assembly.Load(DllName);
Type type = assembly.GetType(TypeName);
object oDbHelper = Activator.CreateInstance(type);
return oDbHelper as IDBHelper;
}
}