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ConstructorInfo Class

Discovers the attributes of a class constructor and provides access to constructor metadata.

Namespace:  System.Reflection
Assembly:  mscorlib (in mscorlib.dll)

[PermissionSetAttribute(SecurityAction.InheritanceDemand, Name = "FullTrust")]
public abstract class ConstructorInfo : MethodBase, 

ConstructorInfo is used to discover the attributes of a constructor as well as to invoke a constructor. Objects are created by calling Invoke on a ConstructorInfo returned by either the GetConstructors or GetConstructor method of a Type object.


ConstructorInfo inherits from MethodBase several members, such as IsGenericMethod, that can be used to examine generic methods. In the .NET Framework version 2.0 constructors cannot be generic, so these members return false or null.

Notes to Inheritors:

When you inherit from ConstructorInfo, you must override the following member overload: Invoke(BindingFlags, Binder, Object[], CultureInfo).

The following example uses ConstructorInfo with GetConstructor and BindingFlags to find the constructors that match the specified search criteria.

using System;
using System.Reflection;
using System.Security;

public class MyClass1
    public MyClass1(int i){}
    public static void Main()
            Type  myType = typeof(MyClass1);
            Type[] types = new Type[1];
            types[0] = typeof(int);
            // Get the public instance constructor that takes an integer parameter.
            ConstructorInfo constructorInfoObj = myType.GetConstructor(
                BindingFlags.Instance | BindingFlags.Public, null,
                CallingConventions.HasThis, types, null);
            if(constructorInfoObj != null)
                Console.WriteLine("The constructor of MyClass1 that is a public " +
                    "instance method and takes an integer as a parameter is: ");
                Console.WriteLine("The constructor of MyClass1 that is a public instance " +
                    "method and takes an integer as a parameter is not available.");
        catch(ArgumentNullException e)
            Console.WriteLine("ArgumentNullException: " + e.Message);
        catch(ArgumentException e)
            Console.WriteLine("ArgumentException: " + e.Message);
        catch(SecurityException e)
            Console.WriteLine("SecurityException: " + e.Message);
        catch(Exception e)
            Console.WriteLine("Exception: " + e.Message);

This type is thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0