C# 覆写操作符= 实例代码

虽然 C# 中不支持直接重载 `=` 赋值操作符，但是我们可以通过实现 `IEquatable<T>` 接口和 `Clone` 方法来实现类的赋值操作。下面是一个例子：

using System;

public class Person : IEquatable<Person>, ICloneable
{
    public string Name { get; set; }
    public int Age { get; set; }

    public bool Equals(Person other)
    {
        if (other == null) return false;
        return (this.Name.Equals(other.Name) && this.Age == other.Age);
    }

    public override bool Equals(object obj)
    {
        if (obj == null) return false;
        Person personObj = obj as Person;
        if (personObj == null) return false;
        else return Equals(personObj);
    }

    public override int GetHashCode()
    {
        return this.Name.GetHashCode() ^ this.Age.GetHashCode();
    }

    public object Clone()
    {
        return new Person { Name = this.Name, Age = this.Age };
    }

    public static bool operator ==(Person person1, Person person2)
    {
        if (((object)person1) == null || ((object)person2) == null)
            return Object.Equals(person1, person2);

        return person1.Equals(person2);
    }

    public static bool operator !=(Person person1, Person person2)
    {
        if (((object)person1) == null || ((object)person2) == null)
            return !Object.Equals(person1, person2);

        return !(person1.Equals(person2));
    }
}

在这个例子中，我们重载了 `==` 和 `!=` 运算符来比较两个 `Person` 对象是否相等。我们也实现了 `IEquatable<T>` 接口和 `Equals` 方法来比较两个 `Person` 对象是否相等。还实现了 `ICloneable` 接口和 `Clone` 方法来实现对象的克隆。这样，我们就可以在需要时使用 `=` 赋值操作符进行类的赋值操作了。例如：

Person person1 = new Person { Name = "Tom", Age = 20 };
Person person2 = new Person { Name = "Tom", Age = 20 };
Person person3 = person1.Clone() as Person;

Console.WriteLine(person1 == person2); // true
Console.WriteLine(person1 == person3); // true

person1.Age = 30;
Console.WriteLine(person1.Age); // 30
Console.WriteLine(person3.Age); // 20

person3 = person1;
Console.WriteLine(person1 == person3); // true