C# 0 The Complete Reference

GetConstructors( )

 on a 

Type

 object. One 

commonly used form is shown here:

ConstructorInfo[ ] GetConstructors( )

It returns an array of 

ConstructorInfo

 objects that describe the constructors.

ConstructorInfo

 is derived from the abstract class 

MethodBase

, which inherits 

MemberInfo

. It also defines several members of its own. The one we are interested in is 

GetParameters( )

, which returns a list of the parameters associated with a constructor. It 

works just like 

GetParameters( )

 defined by 

MethodInfo

, described earlier.

Once an appropriate constructor has been found, an object is created by calling the 

Invoke( )

 method defined by 

ConstructorInfo

. One form is shown here:

object Invoke(object[ ] 

args

)

Any arguments that need to be passed to the method are specified in the array 

args.

 If no 

arguments are needed, pass 

null

 to 

args.

 In all cases, 

args

 must contain exactly the same 

number of elements as there are arguments and the types of arguments must be compatible 

with the types of the parameters. 

Invoke( )

 returns a reference to the object that was 

constructed.

The following program uses reflection to create an instance of 

MyClass

:

// Create an object using reflection.

using System;

using System.Reflection;

class MyClass {

  int x;

  int y;

  public MyClass(int i) {

    Console.WriteLine("Constructing MyClass(int, int). ");

    x = y = i;

  }

  public MyClass(int i, int j) {

    Console.WriteLine("Constructing MyClass(int, int). ");

    x = i;

    y = j;

    Show();

  }

  public int Sum() {

    return x+y;

  }

  public bool IsBetween(int i) {

    if((x < i) && (i < y)) return true;

    else return false;

  }

  public void Set(int a, int b) {

    Console.Write("Inside Set(int, int). ");

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