So I have a delegate
which points to some function which I don't actually know about when I first create the delegate
object. The object is set to some function later.
I also then want to make an expression tree that invokes the delegate with an argument (for this question's sake the argument can be 5
). This is the bit I'm struggling with; the code below shows what I want but it doesn't compile.
Func<int, int> func = null;
Expression expr = Expression.Invoke(func, Expression.Constant(5));
For this example I could do (this is practical since I need to build the expression trees at runtime):
Func<int, int> func = null;
Expression<Func<int>> expr = () => func(5);
This makes expr
become:
() => Invoke(value(Test.Program+<>c__DisplayClass0).func, 5)
Which seems to mean that to use the delegate
func
, I need to produce the value(Test.Program+<>c__DisplayClass0).func
bit.
So, how can I make an expression tree which invokes a delegate?
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