I really wish I could either a) pass an object and a methodinfo as
constructor parameters to a delegate or b) discover the metadata token
for a method from managed code. If I could do a) then I could say this:
uint mydelegate();
object o = new object();
mydelegate d = new mydelegate(o, o.GetType().GetMethod("GetHashCode"));
uint hashcode = d();
Here's an example of why I care. I have a class that implements a bunch
of related methods (all with the same signature). This class stores
delegates to these methods in a hashtable and has a function like:
void Call(string label)
Said class uses the label to key to the desired function. Now, given
the constructor above I could write some really cool code, namely:
public HypotheticalClassCtor()
{
foreach(MethodInfo m in this.GetType().GetMethods())
{
if(m.Name.IndexOf("Routine_") != -1)
{
//Impossible to do from C#!
MyHashTable[m.Name.Substring(9)] = new
SubroutineDelegate(this,m);
}
}
}
void Call(string label)
{
return MyHashTable[label]();
}
This snazzy bit of code would automatically add any routine in my class
that fit a certain naming convention to the hashtable. As it is I have
to manually put a line in the constructor for every routine I want
added. This is functional but isn't very sexy :)
I can get there from here if I can have (b). I can do what I want if
there any way to get the metadata token from a MethodInfo. Then I could
write a little library in IL that would expose a function that would
explicitly create the delegate with the two parameters that C# is
already using. For future versions of the CLR it would be awesome if
delegates just got a constructor that could take a MethodInfo like this.
Clearly the MethodInfo has the right token buried in there
*somewhere*...
Any takers?
Jason
You can read messages from the Advanced DOTNET archive, unsubscribe from Advanced
DOTNET, or
subscribe to other DevelopMentor lists at http://discuss.develop.com.
