实例创建时触发事件 [英] Firing event when instance created
本文介绍了实例创建时触发事件的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
如何在实例创建时触发事件？在C＃
How to Firing event when instance created? in C#
推荐答案
多么奇怪的要求！你不能用普通事件做到这一点，因为在实例构造函数完成之前你不能挂钩处理程序（在此之前没有挂钩处理程序的实例！）
你可以做到，但它必须是一个静态事件：
What an odd request! You can''t do it with "normal" events, because you can''t hook a handler to them until the instance constructor is finished (there is no instance to hook the handler to until then!)
You can do it, but it needs to be a Static Event:
public class XX
{
public static event EventHandler Created;
public string Text { get; set; }
public XX(string n)
{
Text = n;
if (Created != null)
{
Created(this, null);
}
}
}然后你可以勾选它等等：
You can then hook to it and so forth:
XX.Created += new EventHandler(XX_Created);
...
XX x = new XX("ONE");
XX y = new XX("Two");这是一个奇怪的请求。
namespace byMirHassanMoosavi / *这个ProblemSet很简单!! * /
{
#region UsingScope
使用系统;
使用System.Collections.Generic;
使用System.Linq;
使用System.Text;
#endregion
#region ProblemSet
命名空间evtFiring
{
#region SolutionScope
public delegate void OnCreateEvent（）; //委托声明
[Serializable（）]
公共类人员
{
公共静态事件OnCreateEvent CreateEvent; //静态事件声明（委托正在使用中！）
#region Props&Field
public string Name {get;组; }
public string Family {get;组; }
公共字符串SerializableStatus = string.Empty;
#endregion
#region构造函数
public Person（）// default构造函数和事件触发场所
{
this.Name =unknown-name！;
this.Family =unknown-family！;
//使用Lambda Expression声明一个匿名方法
Person.CreateEvent + = new OnCreateEvent（（）= >
{
#region ChangeConsoleTheme
Console.BackgroundColor = ConsoleColor.DarkGreen;
Console.Clear（ ）;
Console.ForegroundColor = ConsoleColor.Green;
#endregion
if（this.GetType（ ）.IsSerializable == true）
this.SerializableStatus =是;
else SerializableStatus =不是;
Console.WriteLine（
\\\\ n创建的人员类实例 - {0} - 使用\\\\ n参与以下信息|> \\\\\\\\\\姓名：{1} \t\r\\\
\t |>家庭：{2} \\\\\\\\\ {1} {2} HashCode Is：{3} \t\r\\\
\ t |> {1} {2}类型为：{4} \\\\\\\\\\\\\ {1} {2} {5} Serializable.\r\\\
，
DateTime.Now.ToString（），
this.Name，this.Family ，
this.GetHashCode（）。ToString（），this.GetType（）。Name，SerializableStatus）;
}）;
/ /首先检查然后点火!!
if（CreateEvent！= null）
{
CreateEvent（）;
}
}
public Person（字符串名称，字符串系列）//主要构造函数
{
this .Name = name;
this.Family = family;
//使用Lambda Expression声明一个匿名方法
Person.CreateEvent + = new OnCreateEvent（（）=>
{
#region ChangeConsoleTheme
Console.BackgroundColor = ConsoleColor.DarkGreen;
Console.Clear（）;
Console.ForegroundColor = ConsoleColor.Green;
#endregion
if（this.GetType（）。IsSerializable == true）
this.SerializableStatus =is;
else SerializableStatus =不是;
Console.WriteLine（
\\\\ n）创建的人员类实例 - {0} - 使用\\\\ n参与以下信息|> \\\\\\\\姓名：{1} \t\r\\\
\t |>家庭：{2} \\\\\\\\\ {1} {2} HashCode Is：{3} \t\r\\\
\ t |> {1} {2}类型为：{4} \\\\\\\\\\\\\ {1} {2} {5} Serializable.\r\\\
，
DateTime.Now.ToString（），
this.Name，this.Family ，
this.GetHashCode（）。ToString（），this.GetType（）。Name，SerializableStatus）;
}）;
/ /首先检查然后点火!!
if（CreateEvent！= null）
{
CreateEvent（）;
}
}
#endregion
}
#endregion
#region使用'解决方案''
类程序
{
static void Main（string [] args）
{
人p =新人（MirHassan，Moosavi）;
控制台。的WriteLine（----------------------------------------------- --------------- ----------）;
//人物p2 =新人物（）;
Console.ReadKey（）;
}
}
#endregion
}
#endregion
}
namespace byMirHassanMoosavi /*This ProblemSet is very Easy!!*/
{
#region UsingScope
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
#endregion
#region ProblemSet
namespace evtFiring
{
#region SolutionScope
public delegate void OnCreateEvent(); //delegate declaration
[Serializable()]
public class Person
{
public static event OnCreateEvent CreateEvent; //static event declaration (delegate in use!)
#region Props & Field
public string Name { get; set; }
public string Family { get; set; }
public string SerializableStatus = string.Empty;
#endregion
#region Constructor
public Person() //default Constructor & event firing place
{
this.Name = "unknown-name!";
this.Family = "unknown-family!";
//Using Lambda Expression for declare an anonymous method
Person.CreateEvent += new OnCreateEvent(() =>
{
#region ChangeConsoleTheme
Console.BackgroundColor = ConsoleColor.DarkGreen;
Console.Clear();
Console.ForegroundColor = ConsoleColor.Green;
#endregion
if (this.GetType().IsSerializable == true)
this.SerializableStatus = "is";
else SerializableStatus = "is not";
Console.WriteLine(
"\r\nThe Instance of Person Class Created in - {0} - with \r\nFollowing Information|>\r\n\r\n\t|> Name: {1}\t\r\n\t|> Family: {2}\t\r\n\r\n\t|> {1} {2} HashCode Is: {3}\t\r\n\t|> {1} {2} Type Is: {4}\t\r\n\t\r\n\t|> {1} {2} {5} Serializable.\r\n",
DateTime.Now.ToString(),
this.Name, this.Family,
this.GetHashCode().ToString(), this.GetType().Name, SerializableStatus);
});
//First Check then fire!!
if (CreateEvent != null)
{
CreateEvent();
}
}
public Person(string name, string family)//Main Constructor
{
this.Name = name;
this.Family = family;
//Using Lambda Expression for declare an anonymous method
Person.CreateEvent += new OnCreateEvent(() =>
{
#region ChangeConsoleTheme
Console.BackgroundColor = ConsoleColor.DarkGreen;
Console.Clear();
Console.ForegroundColor = ConsoleColor.Green;
#endregion
if (this.GetType().IsSerializable == true)
this.SerializableStatus = "is";
else SerializableStatus = "is not";
Console.WriteLine(
"\r\nThe Instance of Person Class Created in - {0} - with \r\nFollowing Information|>\r\n\r\n\t|> Name: {1}\t\r\n\t|> Family: {2}\t\r\n\r\n\t|> {1} {2} HashCode Is: {3}\t\r\n\t|> {1} {2} Type Is: {4}\t\r\n\t\r\n\t|> {1} {2} {5} Serializable.\r\n",
DateTime.Now.ToString(),
this.Name, this.Family,
this.GetHashCode().ToString(), this.GetType().Name, SerializableStatus);
});
//First Check then fire!!
if (CreateEvent != null)
{
CreateEvent();
}
}
#endregion
}
#endregion
#region Using''Solution''
class Program
{
static void Main(string[] args)
{
Person p = new Person("MirHassan", "Moosavi");
Console.WriteLine("------------------------------------------------------------------------");
//Person p2 = new Person();
Console.ReadKey();
}
}
#endregion
}
#endregion
}
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