Shaohen’s C# Documentation

Reflection - obtaining information about a type, comes from the way the reflection process works: A Type object questions and it returns (reflects) the information associated with the type, back to you.

It allows one to learn and use the capabilities of types that are known only at runtime.

Obtaining Information about Members

Once a Type object is obtained, the list of all its methods can be retrived by using the GetMethods() method. It has this form:

MethodInfo[] GetMethods()

It returns an array of MethodInfo objects that describe the methods supported by the invoking type.

Here is a program that uses reflection to obtain the methods supported by a class called MyClass.

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;

namespace AnalyzeMethods
    {
    class MyClass
        {
        int x;
        int y;

        public MyClass(int i, int j)
            {
            x = i; y = j;
            }

        public int sum()
            {
            return x + y;
            }

        public bool isBetween(int i)
            {
            return (x < i && i < y ) ? true : false;
            }
        public void set(int a, int b)
            {
            x = a;
            y = b;
            }

        public void set(double a, double b)
            {
            x = (int)a;
            y = (int)b;
            }

        public void show()
            {
            Console.WriteLine("x: {0}, y: {1}", x, y);

            }
        }

    class RelectionDemo
        {
        static void Main(string[] args)
            {
            Type t = typeof(MyClass);

            Console.WriteLine("Analyzing methods in " + t.Name);
            Console.WriteLine();
            Console.WriteLine("Methods supported: ");

            // 1st way to call
            //MethodInfo[] mi = t.GetMethods();

            // 2nd way to call
            //  Only method declared by MyClass are obtained.
            MethodInfo[] mi = t.GetMethods(BindingFlags.DeclaredOnly | BindingFlags.Public
                | BindingFlags.Instance );

            // Dispaly method information
            foreach (MethodInfo m in mi)
                {
                // Display return type and name
                Console.Write("\t" + m.ReturnType.Name +
                    " " + m.Name + "(");

                // Display parameters
                ParameterInfo[] pi = m.GetParameters();

                for (int i = 0; i < pi.Length; i++)
                    {
                    Console.Write(pi[i].ParameterType.Name +
                        "  " + pi[i].Name);

                    if (i + 1 < pi.Length)
                        Console.Write(", ");
                    }
                Console.WriteLine(")");
                }

            
            }
        }
    }

(Notes obtained from C#: The Complete Reference by Schildt)