如何限制委托方法的数量？

Question

I have a delegate ,and i want it only can be register for 5 times. I know i can set the delegate private and write a AddRegister() method to control the amount of registered method. Have any other ideas ?

Answer 1

You can use GetInvocationList method on the delegate object and then call Count method on it. Something to the effect of the following

Mydel d1 = this.MyMethod;
int count = d1.GetInvocationList().Count();//Here count will be 1

Also I would prefer to have the registration combined with the above functionality in one place similar to the one you mentioned in your question. In this way you need not have to write the count <= 5 condition wherever it is being registered. Hence it will be easier to maintain.

Hope this helps.