[C#]RaiseEvent Extension Method (二)

August 17, 2011

    public static void RaiseEvent(this object obj, EventHandler handler, Func&lt;EventArgs&gt; func)
    {
        if (handler == null)
            return;
        handler(obj, func());
    }

    public static void RaiseEvent&lt;TEventArgs&gt;(this object obj, EventHandler&lt;TEventArgs&gt; handler, TEventArgs e) where TEventArgs : EventArgs
    {
        RaiseEvent(obj, handler, () =&gt; e);
    }

    public static void RaiseEvent&lt;TEventArgs&gt;(this object obj, EventHandler&lt;TEventArgs&gt; handler,Func&lt;TEventArgs&gt; func) where TEventArgs : EventArgs
    {
        if (handler == null)
            return;
        handler(obj, func());
    }
}</pre></div>

namespace ConsoleApplication14 { class Program { static void Main(string[] args) { Person Larry = new Person(); Larry.NameChanged += new EventHandler<NameEventArgs>(Larry_NameChanged); Larry.Name = “Larry”; } static void Larry_NameChanged(object sender, NameEventArgs e) { Console.WriteLine(string.Format(“NameChanged to {0}”, e.Name)); } } public static class ObjectExtension { public static void RaiseEvent(this object obj, EventHandler handler, EventArgs e) { RaiseEvent(obj, handler, () => e); }

    public static void RaiseEvent(this object obj, EventHandler handler, Func&lt;EventArgs&gt; func)
    {
        if (handler == null)
            return;
        handler(obj, func());
    }

    public static void RaiseEvent&lt;TEventArgs&gt;(this object obj, EventHandler&lt;TEventArgs&gt; handler, TEventArgs e) where TEventArgs : EventArgs
    {
        RaiseEvent(obj, handler, () =&gt; e);
    }

    public static void RaiseEvent&lt;TEventArgs&gt;(this object obj, EventHandler&lt;TEventArgs&gt; handler,Func&lt;TEventArgs&gt; func) where TEventArgs : EventArgs
    {
        if (handler == null)
            return;
        handler(obj, func());
    }
}

class NameEventArgs : EventArgs
{
    public string Name { get; set; }
}

class Person
{
    private string _name;
    public string Name
    {
        get
        {
            if (_name == null)
                return string.Empty;
            return _name;
        }
        set
        {
            if (_name != value)
            {
                _name = value;
                this.RaiseEvent(NameChanged, () =&gt; new NameEventArgs() { Name = value });
            }
        }
    }
    public event EventHandler&lt;NameEventArgs&gt; NameChanged;
}

}

CSharp