this关键字：
    1、代表当前类的对象。
    2、在类当中显示的调用本类的构造函数 :this

    1. using System;
    2. using System.Collections.Generic;
    3. using System.Text;
    5. namespace _051_面对对象初级_6_this关键字
    6. {
    7.     class Student
    8.     {
    9.         public Student(string name, int age, char gender, int chinese, int math, int english)
    10.         {
    11.             this.Name = name;
    12.             this.Age = age;
    13.             this.Gender = gender;
    14.             this.Chinese = chinese;
    15.             this.Math = math;
    16.             this.English = english;
    17.         }
    19.         public Student(string name, int chinese, int math, int english) : this(name, 0, ' ', 100, 100, 100)
    20.         {
    21.             //this.Name = name;
    22.             //this.Chinese = chinese;
    23.             //this.Math = math;
    24.             //this.English = english;
    25.         }
    30.         private string _name;
    31.         public string Name
    32.         {
    33.             get { return _name; }
    34.             set { _name = value; }
    35.         }
    37.         private int _age;
    38.         public int Age
    39.         {
    40.             get { return _age; }
    41.             set
    42.             {
    43.                 if (value < 0 || value > 100)
    44.                 {
    45.                     value = 0;
    46.                 }
    47.                 _age = value;
    48.             }
    49.         }
    50.         private char _gender;
    51.         public char Gender
    52.         {
    53.             get
    54.             {
    55.                 if (_gender != '男' && _gender != '女')
    56.                 {
    57.                     return _gender = '×';
    58.                 }
    59.                 return _gender;
    60.             }
    61.             set { _gender = value; }
    62.         }
    63.         private int _chinese;
    64.         public int Chinese
    65.         {
    66.             get { return _chinese; }
    67.             set { _chinese = value; }
    68.         }
    69.         private int _math;
    70.         public int Math
    71.         {
    72.             get { return _math; }
    73.             set { _math = value; }
    74.         }
    75.         private int _english;
    76.         public int English
    77.         {
    78.             get { return _english; }
    79.             set { _english = value; }
    80.         }
    82.         public void SayHello()
    83.         {
    84.             Console.WriteLine("我叫{0}，今天{1}岁了，是个{2}生", this.Name, this.Age, this.Gender);
    85.         }
    87.         public void ShouScore()
    88.         {
    89.             Console.WriteLine("我的总成绩是{0}，平均成绩是{1}", (this.Chinese + this.Math + this.English), (this.Chinese + this.Math + this.English) / 3);
    90.         }
    91.     }
    92. }