C#面向对象--结构

//定义一个公共结构MyStruct
public class MyStruct
{
    public int MyField; //声明一个int类型的公共实例字段
    public void MyFunc() //声明一个公共实例方法
    {
        //do…
    }
}

public struct MyStruct
{
    public int MyNum;
    public string MyStr;

    public static int MyStaticNum = 1;

    public MyStruct(int myNum,string myStr)
    {
        MyNum = myNum;
        MyStr = myStr;
    }

    static MyStruct()
    {
        //对于静态成员，可以直接在声明时初始化，也可以在静态构造函数中初始化
        //MyStaticNum = 1;
    }
}

MyStruct myStruct = new MyStruct(); //调用结构的默认构造函数，此时MyNum为0，MyStr为null
myStruct = default(MyStruct); //与使用new MyStruct()完全等效
myStruct = new MyStruct(1, "1"); //调用结构的自定义构造函数

MyStruct myStruct; //构建结构实例，但不调用构造函数
myStruct.MyNum = 1;
int myNum = myStruct.MyNum; //访问某个实例成员之前需要对其初始化

//当需要修改值类型集合中某个元素的数据时，需要先拿一个变量接收，修改完成后再赋值给集合
MyStruct myStruct = myStructList[0];
myStruct.MyNum = 20;
myStructList[0] = myStruct;

MyStruct? myStruct = null;

public struct MyStruct : IEquatable//实现IEquatable接口用于泛型
{
    public int MyNum;

    public override bool Equals(object obj) //会对实参进行装箱
    {
        if (!(obj is MyStruct))
        {
            return false;
        }
        MyStruct other = (MyStruct)obj; //拆箱
        return this.Equals(other);
    }
    public override int GetHashCode() //避免使用散列集合类时装箱并提供高效实现
    {
        return MyNum.GetHashCode();
    }
    public override string ToString() //避免装箱
    {
        return MyNum.ToString();
    }

    public bool Equals(MyStruct other) //避免比较时实参装箱，避免使用泛型时装箱
    {
        return this.MyNum == other.MyNum;
    }
    public static bool operator ==(MyStruct left, MyStruct right) //比较时通常采用==运算符
    {
        return left.Equals(right);
    }
    public static bool operator !=(MyStruct left, MyStruct right)
    {
        return !(left == right);
    }
}