本文實例為大家分享了C#屬性改變引發(fā)事件示例的具體代碼，供大家參考，具體內(nèi)容如下
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using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace ConsoleApplication15{ class Program { static void Main(string[] args) { Monitor m = new Monitor(); m.PropertyChanging += new Monitor.EventHandler(m_PropertyChanging); m.Year = 2014; m.Year = 1890; m.Year = 2013; } static bool First=false; static void m_PropertyChanging(object sender, PropertyChangingEventArgs e) { if (First==false) { First = true; } else { if (e.NewValue < 1900 || e.NewValue > 3000) e.Cancel = true; } } } //（屬性正在改變的時候）事件數(shù)據(jù) class PropertyChangingEventArgs : EventArgs { //構(gòu)造函數(shù) public PropertyChangingEventArgs(string PropertyName, int OldValue, int NewValue) { _PropertyName = PropertyName; _OldValue = OldValue; _NewValue = NewValue; } //存儲數(shù)據(jù) private string _PropertyName; private int _OldValue; private int _NewValue; private bool _Cancel; //獲取或設(shè)置屬性 public string PropertyName { set { _PropertyName = value; } get { return _PropertyName; } } public int OldValue { set { _OldValue = value; } get { return _OldValue; } } public int NewValue { set { _NewValue = value; } get { return _NewValue; } } public bool Cancel { set { _Cancel = value; } get { return _Cancel; } } } class Monitor { //定義委托 public delegate void EventHandler(object sender, PropertyChangingEventArgs e); //定義事件 public event EventHandler PropertyChanging; //事件處理（用屬性方法） int _YearValue; public int Year { get { return _YearValue; } set { if (_YearValue != value) { if (PropertyChanging != null) { PropertyChangingEventArgs e = new PropertyChangingEventArgs("Year", _YearValue, value); PropertyChanging(this, e); if (e.Cancel) { return; } else { _YearValue = value; } } } } } }} |
以上就是本文的全部內(nèi)容，希望對大家的學(xué)習(xí)有所幫助，也希望大家多多支持服務(wù)器之家。
