public int Add(int a, int b)
{
EventHandler <IntEventArgs> before = this.BeforeAdd;
if (before != null)
{
IntEventArgs e1 = new IntEventArgs {
Number = a
};
before(this, e1);
a = e1.Number; // 重新从事件参数中取值，因为有可能会在事件中修改
}
int c = a + b;
EventHandler <IntEventArgs> after = this.AfterAdd;
if (after != null)
{
IntEventArgs e2 = new IntEventArgs {
Number = c
};
after(this, e2);
c = e2.Number; // 重新从事件参数中取值，因为有可能会在事件中修改
}
return(c);
}
public int Add(int a, int b)
{
EventHandler <IntEventArgs> before = this.BeforeAdd;
if (before != null)
{
IntEventArgs e1 = new IntEventArgs {
Number = a
};
before(this, e1);
a = e1.Number; // 重新从事件参数中取值，因为有可能会在事件中修改
}
return(a + b);
}
void instance_BeforeAdd(object sender, IntEventArgs e)
{
e.Number += 5;
}
void instance_AfterAdd(object sender, IntEventArgs e)
{
e.Number += 20;
}
