static void Main(string[] args)
{
int iValue = 123;
string sValue = "456";
DateTime dtValue = DateTime.Now;
Console.WriteLine("***********CommonMethod***************");
CommonMethod.ShowInt(iValue);
CommonMethod.ShowString(sValue);
CommonMethod.ShowDateTime(dtValue);
Console.WriteLine("***********Object***************");
CommonMethod.ShowObject(iValue);
CommonMethod.ShowObject(sValue);
CommonMethod.ShowObject(dtValue);
Console.WriteLine("***********Generic***************");
GenericMethod.Show <int>(iValue);
GenericMethod.Show <string>(sValue);
GenericMethod.Show <DateTime>(dtValue);
Console.WriteLine(typeof(List <>));
Console.WriteLine(typeof(Dictionary <,>));
Console.ReadKey();
}
static void Main(string[] args)
{
try
{
//var list = new List<int>() { 1, 2, 3, 4 }
//.Select(i => new
//{
// id = i,
// name = "Test" + i
//});
//foreach (var item in list)
//{
// Console.WriteLine(item.id);
// Console.WriteLine(item.name);
//}
//List<int>
Console.WriteLine("欢迎来到.net高级班vip课程，今天是Eleven老师给大家带来的泛型Generic");
int iValue = 123;
string sValue = "456";
DateTime dtValue = DateTime.Now;
object oValue = new object();
Console.WriteLine(typeof(List <int>));
Console.WriteLine(typeof(Dictionary <int, string>));
Console.WriteLine("**************************");
CommonMethod.ShowInt(iValue);
//CommonMethod.ShowInt(sValue);
CommonMethod.ShowString(sValue);
CommonMethod.ShowDateTime(dtValue);
Console.WriteLine("**************************");
CommonMethod.ShowObject(oValue);
CommonMethod.ShowObject(iValue);
CommonMethod.ShowObject(sValue);
CommonMethod.ShowObject(dtValue);
Console.WriteLine("**************************");
GenericMethod.Show <object>(oValue);
GenericMethod.Show <int>(iValue);
GenericMethod.Show(iValue);//类型参数可以省略，由编译器推断出来
//GenericMethod.Show<int>(sValue);//类型参数和参数必须匹配
GenericMethod.Show <string>(sValue);
GenericMethod.Show <DateTime>(dtValue);
Console.WriteLine("**************************");
People people = new People()
{
Id = 11,
Name = "山冈"
};
Japanese japanese = new Japanese()
{
Id = 112,
Name = "鬼子"
};
Chinese chinese = new Chinese()
{
Id = 123,
Name = "口口"
};
Hubei hubei = new Hubei()
{
Id = 123,
Name = "pig猪"
};
//Constraint.Show<People>(people);
Constraint.Show <Chinese>(chinese);
Constraint.Show <Hubei>(hubei);
Constraint.ShowPeople(people);
Constraint.ShowPeople(chinese);
Constraint.ShowPeople(hubei);
//Constraint.ShowInterface<People>(people);//没有实现ISports接口
Constraint.ShowInterface <Chinese>(chinese);
Constraint.ShowInterface <Hubei>(hubei);
Constraint.ShowInterface <Japanese>(japanese);
//Constraint.Show<Japanese>(japanese);//虽然Japanese有ID和Name，但是因为不是People，所以不能调用
//Constraint.Show<int>(iValue);//约束后，只能按约束传递
#region Monitor
{
long commonTime = 0;
long objectTime = 0;
long genericTime = 0;
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (int i = 0; i < 1000000000; i++)
{
ShowCommon(iValue);
}
stopwatch.Stop();
commonTime = stopwatch.ElapsedMilliseconds;
}
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (int i = 0; i < 1000000000; i++)
{
ShowObject(iValue);
}
stopwatch.Stop();
objectTime = stopwatch.ElapsedMilliseconds;
}
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (int i = 0; i < 1000000000; i++)
{
ShowGeneric <int>(iValue);
}
stopwatch.Stop();
genericTime = stopwatch.ElapsedMilliseconds;
}
Console.WriteLine("commonTime = {0} objectTime = {1} genericTime = {2}", commonTime, objectTime, genericTime);
}
#endregion
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Console.Read();
}
static void Main(string[] args)
{
try
{
{
Console.WriteLine("*****************Old Way***********");
int i = 123;
string s = "456";
DateTime dt = DateTime.Now;
object o = "sorry";
{
Console.WriteLine("************************");
CommonMethod.ShowInt(i);
CommonMethod.ShowString(s);
CommonMethod.ShowDateTime(dt);
CommonMethod.ShowObject(o);
CommonMethod.ShowObject(i);
CommonMethod.ShowObject(s);
}
{
Console.WriteLine("*************Generic**************");
GenericMethod.Show(i); // <> 能省略，自动推算
GenericMethod.Show <string>(s); //需要指定参数类型
}
{
Console.WriteLine("*************Monitor**************");
// 性能 common ~ Generic > object
Monitor.Show();
GenericCacheTest.Show();
}
{
Console.WriteLine("********************Constraint*************");
{
People people = new People()
{
Id = 123,
Name = "people"
};
Chinese chinese = new Chinese()
{
Id = 234,
Name = "Ivan"
};
Hubei hubei = new Hubei()
{
Id = 345,
Name = "Hubei"
};
Japanese japanese = new Japanese()
{
Id = 567,
Name = "Cang"
};
CommonMethod.ShowObject(people);
CommonMethod.ShowObject(chinese);
CommonMethod.ShowObject(hubei);
CommonMethod.ShowObject(japanese);
GenericMethod.Show <People>(people);
GenericMethod.Show <Chinese>(chinese);
GenericMethod.Show <Hubei>(hubei);
GenericMethod.Show <Japanese>(japanese);
{
Constraint.Show <People>(people);
Constraint.Show <Chinese>(chinese);
Constraint.Show <Hubei>(hubei);
// Constraint.Show<Japanese>(japanese); Error because Japanese not a child class of People
}
}
{
}
}
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
Console.Read();
}
static void Main(string[] args)
{
Console.WriteLine(".net framework 1.0的时候");
int intValue = 1;
string stringValue = "1";
DateTime dateValue = DateTime.Now;
CommonMethod.ShowInt(intValue);
CommonMethod.ShowString(stringValue);
CommonMethod.ShowDateTime(dateValue);
Console.WriteLine("使用object简化代码");
CommonMethod.ShowObj(intValue);
CommonMethod.ShowObj(stringValue);
CommonMethod.ShowObj(dateValue);
Console.WriteLine(".net framework 2.0的时候，引入泛型");
GenericMethod.Show(intValue);
GenericMethod.Show(stringValue);
GenericMethod.Show(dateValue);
Console.WriteLine("打印泛型类型，会看到编译器，生成占位符");
Console.WriteLine(typeof(List <>));
Console.WriteLine(typeof(Dictionary <,>));
Console.WriteLine("比较性能");
Monitor.Show();
// 泛型类
// 泛型接口
// 泛型约束
var people = new People()
{
Id = 1,
Name = "人类"
};
var chinese = new Chinese()
{
Id = 2,
Name = "中国人"
};
var japanese = new Japanese()
{
Id = 3,
Name = "日本人"
};
CommonMethod.ShowObj(people);
CommonMethod.ShowObj(chinese);
CommonMethod.ShowObj(japanese);
GenericMethod.Show(people);
GenericMethod.Show(chinese);
GenericMethod.Show(japanese);
// 上面方法只是打印了对象的类型
// 如果想打印 对象里的内容 输出Id,Name的值
Constraint.ShowBase(people);
Constraint.Show(chinese);
//Constraint.Show(japanese); 由于japannese 不是继承自 People 类所以这里不能使用
// 为啥不直接使用基类 方法
// 泛型类缓存
GenericCacheTest.Show();
}
static void Main(string[] args)
{
try
{
int iValue = 123;
string sValue = "456";
DateTime dtValue = DateTime.Now;
object oValue = new object();
Console.WriteLine(typeof(List <int>));
Console.WriteLine(typeof(Dictionary <string, int>));
Console.WriteLine("*************************************");
CommonMethod.ShowInt(iValue);
CommonMethod.ShowString(sValue);
CommonMethod.ShowDateTime(dtValue);
Console.WriteLine("*************************************");
CommonMethod.ShowObject(oValue);
CommonMethod.ShowObject(iValue);
CommonMethod.ShowObject(sValue);
CommonMethod.ShowObject(dtValue);
Console.WriteLine("*************************************");
GenericMethod.Show <object>(oValue);
GenericMethod.Show <int>(iValue);
GenericMethod.Show(iValue);//类型参数可以省略，由编译器推断
GenericMethod.Show <string>(sValue);
GenericMethod.Show <DateTime>(dtValue);
Console.WriteLine("*************************************");
GenericConstraint.Show <People>(new People {
Id = 1001, Name = "lucy"
});
GenericConstraint.Show <Chinese>(new Chinese {
Id = 1002, Name = "Coco"
});
GenericConstraint.Show <JiangXi>(new JiangXi {
Id = 1003, Name = "Jack"
});
//GenericConstraint.Show<int>(1);//约束后，只能按约束传递
//GenericConstraint.ShowInterface<People>(new People { Id = 1001, Name = "lucy" });
GenericConstraint.ShowInterface <Chinese>(new Chinese {
Id = 1002, Name = "Coco"
});
GenericConstraint.ShowInterface <JiangXi>(new JiangXi {
Id = 1003, Name = "Jack"
});
GenericConstraint.ShowInterface <Japanese>(new Japanese {
Id = 1004, Name = "鬼子"
});
#region Monitor
long commonTime = 0;
long objectTime = 0;
long genericTime = 0;
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (int i = 0; i < 1000000000; i++)
{
ShowCommon(iValue);
}
stopwatch.Stop();
commonTime = stopwatch.ElapsedMilliseconds;
}
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (int i = 0; i < 1000000000; i++)
{
ShowObject(oValue);//装箱，值类型是分配在栈上的，引用类型是分配在堆上的
}
stopwatch.Stop();
objectTime = stopwatch.ElapsedMilliseconds;
}
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (int i = 0; i < 1000000000; i++)
{
ShowGeneric <int>(iValue);
}
stopwatch.Stop();
genericTime = stopwatch.ElapsedMilliseconds;
}
Console.WriteLine("commonTime={0} objectTime={1} genericTime={2}", commonTime, objectTime, genericTime);
#endregion
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Console.Read();
}
static void Main(string[] args)
{
int iValue = 123;
string sValue = "abc";
DateTime dtValue = DateTime.Now;
Console.WriteLine("****************常规调用****************");
{
CommonMethod.ShowInt(iValue);
CommonMethod.ShowString(sValue);
CommonMethod.ShowDateTime(dtValue);
}
Console.WriteLine("****************object调用****************");
{
CommonMethod.ShowObject(iValue);
CommonMethod.ShowObject(sValue);
CommonMethod.ShowObject(dtValue);
}
Console.WriteLine("****************泛型调用****************");
{
GenericMethod.Show <int>(iValue);
GenericMethod.Show(sValue); // 可以省略，自动推算
GenericMethod.Show <DateTime>(dtValue);
}
Console.WriteLine("****************Monitor****************");
{
Monitor.Show(iValue);
}
Console.WriteLine("****************约束****************");
{
People people = new People
{
Id = 11,
Name = "张三"
};
Teacher teacher = new Teacher
{
Id = 12,
Name = "李老师"
};
Student student = new Student
{
Id = 13,
Name = "赵同学"
};
//Constraint.Show<People>(people);
Constraint.Show <Teacher>(teacher);
//Constraint.Show<Student>(student);
}
Console.WriteLine("****************协变&异变****************");
{
People people = new Teacher();
//IList<People> peoples = new List<Teacher>();
IEnumerable <People> peoples = new List <Teacher>();
}
Console.WriteLine("****************泛型缓存****************");
{
for (int i = 0; i < 5; i++)
{
Console.WriteLine(GenericCache <int> .GetCache());
Thread.Sleep(10);
Console.WriteLine(GenericCache <long> .GetCache());
Thread.Sleep(10);
Console.WriteLine(GenericCache <DateTime> .GetCache());
Thread.Sleep(10);
Console.WriteLine(GenericCache <string> .GetCache());
Thread.Sleep(10);
}
}
Console.WriteLine("****************Monitor****************");
{
Monitor.Show();
}
}
static void Main(string[] args)
{
try
{
// 欢迎大家来到.Net 高级班的Vip课程，我是Richard老师！
// 今天是第十三期的第一次课：泛型
//什么是泛型？
//宽泛的，不确定的，就是不确定的类型
//List<string> intlist = new List<string>();
// var i = 1234; // 语法糖
Console.WriteLine(typeof(List <>));
Console.WriteLine(typeof(Dictionary <,>));
Console.WriteLine("欢迎来到.net高级班vip课程，今天是Richard老师给大家带来的泛型Generic");
int iValue = 123;
string sValue = "456";
DateTime dtValue = DateTime.Now;
object oValue = "789";
Console.WriteLine("***********************Common***********************");
CommonMethod.ShowInt(iValue);
CommonMethod.ShowString(sValue);
CommonMethod.ShowDateTime(dtValue);
Console.WriteLine("***********************Object***********************");
CommonMethod.ShowObject(oValue);
CommonMethod.ShowObject(iValue);
CommonMethod.ShowObject(sValue);
CommonMethod.ShowObject(dtValue);
Console.WriteLine("***********************Generic***********************");
// 泛型只有：泛型方法、泛型类、泛型接口、泛型委托
//泛型方法调用的时候，需要加上<>,而且需要指定具体的类型、指定的类型和传入的参数类型保持一致。
CommonMethod.Show(iValue); //如果类型参数，可以通过参数类型推导出来，那么就可以省略
/* CommonMethod.Show<int>(sValue);*/ // 因为类型错了
CommonMethod.Show(sValue);
CommonMethod.Show <DateTime>(dtValue);
CommonMethod.Show <object>(oValue);
//Monitor.Show();
Console.WriteLine("***********************GenericCache***********************");
//GenericCacheTest.Show();
//泛型方法 一个方法满足多个类型的需求
//泛型类 就是一个类 满足多个类型的需求
//泛型接口 就是一个接口 满足多个多个类型的需求
//泛型委托 就是一个委托 满足多个多个类型的需求
//GenericConstraint.ShowObject(iValue);
//GenericConstraint.ShowObject(sValue);
//GenericConstraint.ShowObject(dtValue);
//GenericConstraint.ShowObject(oValue);
Console.WriteLine("***********************GenericConstraint***********************");
// 泛型约束的好处：
// 加了约束以后可以获取更多的功能；
// 程序在调用的时候可以避免错误调用
People people = new People()
{
Id = 123,
Name = "Richard"
};
Chinese chinese = new Chinese()
{
Id = 234,
Name = "习大大"
};
Hubei hubei = new Hubei()
{
Id = 345,
Name = "王市长"
};
Japanese japanese = new Japanese()
{
Id = 678,
Name = "福原爱"
};
// Object 方法因为可以出入任何类型，没有限制，如果传入的类型不匹配，就会发生异常（类型安全问题）
//GenericConstraint.ShowObject(people);
//GenericConstraint.ShowObject(chinese);
//GenericConstraint.ShowObject(hubei);
//GenericConstraint.ShowObject(japanese);
//GenericConstraint.Show(people);
//GenericConstraint.Show(chinese);
//GenericConstraint.Show(hubei);
//GenericConstraint.Show(japanese);//
// GenericConstraint.GenericShow(123);
GenericConstraint.GenericShow(people);
GenericConstraint.GenericShow(chinese);
GenericConstraint.GenericShow(hubei);
GenericConstraint.GenericShow(japanese);//
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Console.Read();
}