C#this的五種用法

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this的五種用法：

1.使用被掩蓋的成員變數：

class AA

{

        int a;

        public void set1(int a)

        {

            this.a = a;//right

        }

        public void set2(int a)

        {

            a = a;//會有警告：“對同一變數進行賦值；是否希望對其他變數賦值?”；

        }

}

2.把這個對象傳給其他函數

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace ConsoleApplication1{    class BB    {        static public void set(AA t,int a)        {            t.set1(a);        }    }    class AA    {        int a;        public void set1(int a)        {            this.a = a;        }        public void set2(int a)        {            BB.set(this, a);        }        public int get()        {            return a;        }    }        class Program    {        static void Main(string[] args)        {            AA t = new AA();            t.set2(123);            Console.WriteLine(t.get());        }    }}

 

3.With Indexers(索引器)//這個暫時不懂

4.調用其他建構函式

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace ConsoleApplication2{    class AA    {        int a, b;        public AA(int a)        {            this.a = a;            b = -1;            print();        }        public AA(int a,int b):this(a)        {            this.b = b;            print();        }        void print()        {            Console.WriteLine("{0} {1}", a, b);        }    }    class Program    {        static void Main(string[] args)        {            AA t = new AA(1);            t = new AA(1, 1);        }    }}

輸出：

1 -1

1 -1

1 1

5.是代碼更明確

如把

        public AA(int a)        {            this.a = a;            b = -1;            print();        }    

改為

        public AA(int a)        {            this.a = a;            this.b = -1;            print();        }

 

C#this的五種用法