我已经阅读了很多文章,但我仍然不清楚我们通常创建的普通委托和多播委托之间的区别.
public delegate void MyMethodHandler(object sender);
MyMethodHandler handler = new MyMethodHandler(Method1);
handler += Method2;
handler(someObject);
上面的委托MyMethodHandler将调用这两个方法.
我已经阅读了很多文章,但我仍然不清楚我们通常创建的普通委托和多播委托之间的区别.
public delegate void MyMethodHandler(object sender);
MyMethodHandler handler = new MyMethodHandler(Method1);
handler += Method2;
handler(someObject);
上面的委托MyMethodHandler将调用这两个方法.
This article很好地解释了这一点:
delegate void Del(string s);
class TestClass
{
static void Hello(string s)
{
System.Console.WriteLine(" Hello, {0}!", s);
}
static void Goodbye(string s)
{
System.Console.WriteLine(" Goodbye, {0}!", s);
}
static void Main()
{
Del a, b, c, d;
// Create the delegate object a that references
// the method Hello:
a = Hello;
// Create the delegate object b that references
// the method Goodbye:
b = Goodbye;
// The two delegates, a and b, are composed to form c:
c = a + b;
// Remove a from the composed delegate, leaving d,
// which calls only the method Goodbye:
d = c - a;
System.Console.WriteLine("Invoking delegate a:");
a("A");
System.Console.WriteLine("Invoking delegate b:");
b("B");
System.Console.WriteLine("Invoking delegate c:");
c("C");
System.Console.WriteLine("Invoking delegate d:");
d("D");
}
}
/* Output:
Invoking delegate a:
Hello, A!
Invoking delegate b:
Goodbye, B!
Invoking delegate c:
Hello, C!
Goodbye, C!
Invoking delegate d:
Goodbye, D!
*/