What does () => mean in C#?

Question

I\'ve been reading through the source code for Moq and I came across the following unit test:

Assert.Throws(() => Times         


        

Answer 1

It's a lambda expression. The most common syntax is using a parameter, so there are no parentheses needed around it:

n => Times.AtLeast(n)

If the number of parameters is something other than one, parentheses are needed:

(n, m) => Times.AtLeast(n + m)

When there are zero parameters, you get the somewhat awkward syntax with the parentheses around the empty parameter list:

() => Times.AtLeast(0)