How to list fields of current class in C# Reflection (problem with this.GetType())?

Question

This is accepted by the compiler:

FieldInfo[] fieldInfos;
fieldInfos = typeof(MyClass).GetFields(BindingFlags.NonPublic | BindingFlags.Instance);

This is NOT accepted by the compiler:

FieldInfo[] fieldInfos;
fieldInfos = typeof(this.GetType()).GetFields(BindingFlags.NonPublic | BindingFlags.Instance);

How to fix second syntax?

Answer 1

You don't need typeof() around a GetType call since it already returns a Type object. typeof is a special syntax for getting a Type object from a type name, without having to do something like Type.GetType("Foo") .

FieldInfo[] fieldInfos;
fieldInfos = GetType().GetFields(BindingFlags.NonPublic |
                                 BindingFlags.Instance);

Answer 2

typeof does not permit you to pass in an instance of System.Type . typeof is an operator whose sole parameter is a type (like Int32 , or object , or MyClass ) and it returns an instance of System.Type . When you already have an instance of an object, just call GetType so get an instance of System.Type . Therefore, just say

fieldInfos = this.GetType()
                 .GetFields(BindingFlags.NonPublic | BindingFlags.Instance);

Answer 3

You don't need the typeof in the second example. Just use:

 FieldInfo[] fieldInfos = this.GetType().GetFields(BindingFlags.NonPublic |
                                                   BindingFlags.Instance);

The point of typeof is it's a sort of "literal" format for obtaining a Type reference. GetType() already returns a type, so you don't need it.

To put it another way, suppose you wanted a string... you wouldn't use:

string x = "y.ToString()";

you'd just use

string x = y.ToString();

Replace the quotes with typeof() and it's the same sort of thing...

Answer 4

FieldInfo[] fieldInfos = this.GetType().GetFields(BindingFlags.NonPublic | BindingFlags.Instance);