C# 自定义异常总结及严格遵循几个原则

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;

using System.Runtime.Serialization.Formatters.Binary;

namespace ConsoleApplication3

{

[Serializable] //声明为可序列化的 因为要写入文件中

public class PayOverflowException : ApplicationException//由用户程序引发，用于派生自定义的异常类型

{

/// <summary>

/// 默认构造函数

/// </summary>

public PayOverflowException() { }

public PayOverflowException(string message)

: base(message) { }

public PayOverflowException(string message, Exception inner)

: base(message, inner) { }

//public PayOverflowException(System.Runtime.Serialization.SerializationInfo info,

// System.Runtime.Serialization.StreamingContext context)

// : base(info, context) { }

}

internal class Employee

{

public int ID { get; set; }

public string Name { get; set; }

/// <summary>

/// current pay

/// </summary>

public int CurrPay { get; set; }

public Employee() { }

public Employee(int id, string name, int currpay)

{

this.ID = id;

this.Name = name;

this.CurrPay = currpay;

}

/// <summary>

/// 定义一个GiveBunus的虚方法以供不同的派生类进行重载

/// </summary>

/// <param name="amount">奖金额度</param>

public virtual void GiveBunus(int amount)

{

//用一个临时变量记录递增之前的值

var pay = CurrPay;

this.CurrPay += amount;

if (CurrPay > 10000)

{

//发生异常,将CurrPay的值进行恢复,

//并抛出异常,外部程序捕获次异常

this.CurrPay = pay;

var ex = new PayOverflowException("The employee's max pay should be no more than 10000.");

throw ex;

}

}

}

class Program

{

static void Main(string[] args)

{

Console.WriteLine("**** 创建Employee对象，并用try/catch捕获异常 *****");

var emp = new Employee(10001, "Yilly", 8000);

try

{

emp.GiveBunus(3000);

}

catch (PayOverflowException ex)

{

Console.WriteLine("异常信息:{0}\n发生于{1}类的{2}方法", ex.Message,

ex.TargetSite.DeclaringType, ex.TargetSite.Name);

try

{

var file = new FileStream(@"c:\customerexception.txt", FileMode.Create);

//*** 异常信息写入文件中的代码省略...

//以序列化方式写入

BinaryFormatter bf = new BinaryFormatter();

bf.Serialize(file, ex);

file.Close();

//以字节方式写入

//byte[] buffer = System.Text.Encoding.Default.GetBytes(ex.Message);

//int leng = 0;

//leng = buffer.GetLength(0);

//file.Write(buffer, 0, leng);

//file.Close();

}

catch (Exception ex1)

{

var inner = new PayOverflowException(ex.Message, ex1);

throw inner;

}

}

}

}

}