ASP.NETCore1C#6.0新语法

1.字符串嵌入值(String interpolation)

            Console.WriteLine($"年龄:{{{this.Age}}}  生日:{{{this.BirthDay.ToString("yyyy -MM-dd")}}}");
            Console.WriteLine($"{(this.Age <= 22 ? "小鲜肉" : "老鲜肉")}");

2.导入静态类(Using Static)

using static System.Math;            

            Console.WriteLine($"之前的使用方式: {Math.Pow(4, 2)}");
            Console.WriteLine($"导入后可直接使用方法: {Pow(4, 2)}");

3.空值运算符(Null-conditional operators)

            int? iValue = 10;
            Console.WriteLine(iValue?.ToString());//不需要判断是否为空
            string name = null;
            Console.WriteLine(name?.ToString());

4.对象初始化器(Index Initializers)

            IDictionary<int, string> dictOld = new Dictionary<int, string>()
            {
                { 1,"first"},
                { 2,"second"}
            };

            IDictionary<int, string> dictNew = new Dictionary<int, string>()
            {
                [4] = "first",
                [5] = "second"
            };

5.异常过滤器(Exception filters)

            int exceptionValue = 10;
            try
            {
                Int32.Parse("s");
            }
            catch (Exception e) when (exceptionValue > 1)//满足条件才进入catch
            {
                Console.WriteLine("catch");
                //return;
            }

6.nameof表达式 (nameof expressions)，方便修改变量名

            string str = "哈哈哈哈";
            Console.WriteLine($"变量str值为：{str}");
            Console.WriteLine($"变量{nameof(str)}值为：{str}");

7.在属性/方法里使用Lambda表达式(Expression bodies on property-like function members)

public string NameFormat => string.Format("姓名: {0}", "summit");
public void Print() => Console.WriteLine(Name);