Example #1
0
        static void Main(string[] args)
        {
            {
                Console.WriteLine("***************Lambda*****************");
                LambdaShow lambdaShow = new LambdaShow();
                lambdaShow.Show();
            }
            {
                object o1 = new
                {
                    Id  = 3,
                    age = 25
                };
                // o1.Id  //not work

                dynamic o2 = new
                {
                    Id  = 3,
                    age = 25
                };

                Console.WriteLine(o2.Id); //dynamic could ignore the compiler checking.

                var o3 = new
                {
                    Id  = 3,
                    age = 25
                };

                Console.WriteLine(o3.Id); //dynamic could ignore the compiler checking.
            }
            #region ExtendMethod
            {
                Student student = new Student()
                {
                    Id      = 1,
                    Name    = "Jason",
                    Age     = 25,
                    ClassId = 2
                };

                string s = null;
                student.Study();
                student.StudyHard();
                //又要增加方法  又不想(不能)修改
                student.Sing();
                ExtendMethod.Sing(student);

                int?iValue = null;
                int r1     = iValue.ToInt(0);

                int  i1 = 2, i2 = 4;
                bool r2 = i1.greaterThan(i2);

                int r3 = student.Length();
            }
            #endregion

            #region linq
            {
                Console.WriteLine("***************Linq*****************");
                LinqShow show = new LinqShow();
                show.Show();
            }
            #endregion


            Console.Read();
        }
Example #2
0
        static void Main(string[] args)
        {
            try
            {
                Console.WriteLine("欢迎来到.net高级班vip课程,今天是Eleven老师为大家带来的linq课程");

                //{
                //    Console.WriteLine("***************Lambda*****************");
                //    LambdaShow lambdaShow = new LambdaShow();
                //    lambdaShow.Show();
                //}

                #region 匿名类 var
                //{
                //    Student student = new Student()
                //    {
                //        Id = 1,
                //        Name = "大水治禹",
                //        Age = 25,
                //        ClassId = 2
                //    };
                //    student.Study();

                //    //匿名类 3.0
                //    object model = new//3.0
                //    {
                //        Id = 2,
                //        Name = "undefined",
                //        Age = 25,
                //        ClassId = 2
                //    };
                //    //Console.WriteLine(model.Id);//object 编译器不允许
                //    var varModel = new//3.0  编译后是有一个真实的类
                //    {
                //        Id = 2,
                //        Name = "undefined",
                //        Age = 25,
                //        ClassId = 2
                //    };
                //    Console.WriteLine(varModel.Id);
                //    //varModel.Id = 123;//只能get 没有set
                //    //反射可以找到

                //dynamic dModel = new//4.0
                //{
                //    Id = 2,
                //    Name = "undefined",
                //    Age = 25,
                //    ClassId = 2
                //};
                //var s = dModel;
                //    ////dModel.Id = 3;//实例是只读的,所以不能赋值
                //    Console.WriteLine(dModel.Id);
                //    ////Console.WriteLine(dModel.Eleven);

                //    int i2 = 2;
                //    var i1 = 1;//var就是个语法糖,由编译器自动推算
                //    var s = "Eleven";

                //    //var aa;//var必须在声明的时候就确定类型
                //    //s = 123;//确定类型后是不能改的

                //    //1 var 配合匿名类型使用
                //    //2 var 偷懒,复杂类型的使用
                //    //var varModel = new//3.0
                //    //{
                //    //    Id = 2,
                //    //    Name = "undefined",
                //    //    Age = 25,
                //    //    ClassId = 2
                //    //};
                //    //Console.WriteLine(varModel.Id);

                //    //var和object 和dynamic
                //}
                #endregion

                #region 扩展方法 3.0
                {
                    //Student student = new Student()
                    //{
                    //    Id = 1,
                    //    Name = "大水治禹",
                    //    Age = 25,
                    //    ClassId = 2
                    //};

                    //string s = null;
                    //student.Study();
                    //student.StudyHard();
                    ////又要增加方法  又不想(不能)修改
                    //student.Sing();

                    //ExtendMethod.Sing(student);
                    //Nullable<int>
                    int?iValue1 = null;
                    //int? iValue = 2;
                    //iValue1.ToInt();

                    //iValue1.Length();
                    //student.Length();
                    //s.Length();

                    //123.Than(234);
                }
                #endregion

                #region linq
                {
                    Console.WriteLine("***************Linq*****************");
                    LinqShow show = new LinqShow();
                    show.Show();
                }
                #endregion

                #region yield
                {
                    Console.WriteLine("***************Yield*****************");
                }

                #endregion
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            Console.Read();
        }
Example #3
0
        static void Main(string[] args)
        {
            try
            {
                Console.WriteLine("欢迎来到.Net高级班vip课程,今天是Eleven老师为大家带来的linq课程");
                {
                    //Console.WriteLine("***************Lambda*****************");
                    //LambdaShow lambdaShow = new LambdaShow();
                    //lambdaShow.Show();
                }

                #region 3.0出了个匿名类 var
                //{
                //    Console.WriteLine("*****************匿名类**************");
                //    Student student = new Student()
                //    {
                //        Id = 1,
                //        Name = "斤宝PAPI",
                //        Age = 25,
                //        ClassId = 2
                //    };
                //    student.Study();

                //    //匿名类
                //    //object model = new //3.0
                //    //{
                //    //    Id = 2,
                //    //    Name = "undefined",
                //    //    Age = 25,
                //    //    ClassId = 2,
                //    //    Teacher="Eleven"
                //    //};
                //    //Console.WriteLine(model.Id);
                //    //Console.WriteLine(model, Name);
                //    //C#强类型语言,编译时会确定类型,object 决定了没有Id属性
                //    //运行时确实有Id和Name  但是编译器不认可

                //    //dynamic避开编译器检查
                //    //dynamic dModel = new//4.0
                //    //{
                //    //    Id = 2,
                //    //    Name = "undefined",
                //    //    Age = 25,
                //    //    ClassId = 2
                //    //};
                //    //Console.WriteLine(dModel.Id);
                //    //Console.WriteLine(dModel.Name);
                //    ////dModel.Study();
                //    Console.WriteLine("&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&");
                var model = new //3.0
                {
                    Id      = 2,
                    Name    = "undefined",
                    Age     = 25,
                    ClassId = 2,
                    Teacher = "Eleven"
                };
                //    Console.WriteLine(model.Id);
                //    Console.WriteLine(model.Teacher);
                //    Console.WriteLine(model.GetType().Name);
                //    //model.Id = 3;//只读  只有初始化的时候指定

                //    Console.WriteLine("&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&");
                //    int i2 = 2;
                //    var i1 = 1;//var就是个语法糖,由编译器自动推算
                //    var s = "Eleven";
                //    //var aa;//var声明的变量必须初始化,必须能推算出类型

                //    ////1 var 配合匿名类型使用
                //    ////2 var 偷懒,复杂类型的使用
                //    //var varModel = new//3.0
                //    //{
                //    //    Id = 2,
                //    //    Name = "undefined",
                //    //    Age = 25,
                //    //    ClassId = 2
                //    //};
                //    //Console.WriteLine(varModel.Id);
                //    ////varModel.Id = 3;//只读属性
                //    ////Console.WriteLine(varModel.Eleven);
                //}
                #endregion

                #region 扩展方法 3.0
                {
                    //Student student = new Student()
                    //{
                    //    Id = 1,
                    //    Name = "大水治禹",
                    //    Age = 25,
                    //    ClassId = 2
                    //};
                    //student.Study();
                    ////ExtendMethod.StudyPractise(student);
                    //student.StudyPractise();
                    ////扩展方法调用,很像实例方法,就像扩展了Student的逻辑
                    ////1 第三方的类,不适合修改源码,可以通过扩展方法增加逻辑
                    ////优先调用实例方法,最怕扩展方法增加了,别人类又修改了
                    ////2 适合组件式开发的扩展(.NetCore),定义接口或者类,是按照最小需求,但是在开发的时候又经常需要一些方法,就通过扩展方法 context.Response.WriteAsync  中间件的注册
                    ////3 扩展一些常见操作
                    ////会污染基础类型,一般少为object  没有约束的泛型去扩展
                    //int? k = 23;
                    //int l = 4;
                    //int r = k.ToInt() + l;
                    //string result = "2342543546546464564656".ToLength(20);

                    //k.ToStringCustom();
                    //l.ToStringCustom();
                    //result.ToStringCustom();
                    //object o = "";
                    ////o.
                    ////k.
                }
                #endregion

                #region linq
                {
                    Console.WriteLine("***************Linq*****************");
                    LinqShow show = new LinqShow();
                    show.Show();
                }
                #endregion

                #region yield
                {
                    Console.WriteLine("***************Yield*****************");
                    foreach (var item in new YieldShow().YieldMethod())
                    {
                        Console.WriteLine(item);
                    }
                    foreach (var item in new YieldShow().CommonMethod())
                    {
                        Console.WriteLine(item);
                    }

                    new YieldShow().Show();
                }

                #endregion
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            Console.Read();
        }