类的StackOverflowException [英] StackOverflowException with class

问题描述

我写的课程有问题.当我尝试调用它时，出现异常.请参阅下面的代码以更清楚.
我上课了:

I have a problem with a class that I wrote. When I try to call it I get an exception. See the code below for more clarity.
I have the class:

using System;
using System.Data;

namespace People
{
class Person
{
    // Auto prop + field
    public string Name
    {
        get { return this.Name; }
        private set
        {
            if (string.IsNullOrEmpty(value))
            {
                throw new NoNullAllowedException("Name is mandatory");
            }
            else
            {
                this.Name = value;
            }
        }
    }

    // Auto prop + field
    public int Age
    {
        get { return this.Age; }
        private set
        {
            if (value <= 0 || value > 100)
            {
                throw new Exception("Age must be between 1 and 100");
            }
            else
            {
                this.Age = value;
            }
        }
    }

    // Auto prop + field
    public string Email
    {
        get { return this.Email; }
        private set { this.Email = value; }
    }

    // Constructor 1
    public Person(string name, int age, string email)
    {
        this.Name = name;
        this.Age = age;
        this.Email = email;
    }

    // Constructor 2
    public Person(string name, int age) : this(name,age,"")
    {
    }

    // Write to console
    public override string ToString()
    {
        return string.Format("Name: {0} \nAge: {1} \nEmail: {2}" ,Name,Age,Email);
    }
}
}

当我叫这堂课时:

Person someone = new Person("First Someone",51,"[e-mail]");
Console.WriteLine(someone);

我得到:

进程由于StackOverflowException而终止.

Process is terminated due to StackOverflowException.

我看不到问题.
预先谢谢你.

I can't see the problem.
Thank you in advance.

推荐答案

问题是，当您尝试获取或设置任何属性(例如 Name )时，存在一个代码路径调用具有相同属性的设置器:

The problem is that when you try to get or set any of the properties, say, Name, there is a code path that calls the setter of the same property:

public string Name
{
    get { return this.Name; } // <<<<====== HERE
    private set
    {
        if (string.IsNullOrEmpty(value))
        {
            throw new NoNullAllowedException("Name is mandatory");
        }
        else
        {
            this.Name = value; // <<<<==== HERE
        }
    }
}

this.Name 的意思是用 value 的值调用 Name 的获取器/设置器".这将导致无限递归，从而导致堆栈溢出.

this.Name means "call getter/setter of Name with the value of value". This creates infinite recursion, causing stack overflow.

要使用诸如此类的条件来实现属性，您需要定义存储实际数据的字段.一种常见的方法是将这些字段设为私有，并使用与属性相同的名称来命名它们，但首字母不应大写:

To implement properties with conditions like that you need to define fields that store the actual data. A common approach is to make these fields private, and name them with the same name as the property, except the first letter should not be capitalized:

private string name; // <<<<==== Add this
public string Name
{
    get { return name; } // <<<<====== change
    private set
    {
        if (string.IsNullOrEmpty(value))
        {
            throw new NoNullAllowedException("Name is mandatory");
        }
        else
        {
            name = value; // <<<<==== change
        }
    }
}

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