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Type.GetMethod Method (String, BindingFlags, Binder, CallingConventions, Type[], ParameterModifier[])

Searches for the specified method whose parameters match the specified argument types and modifiers, using the specified binding constraints and the specified calling convention.

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

public MethodInfo GetMethod (
	string name,
	BindingFlags bindingAttr,
	Binder binder,
	CallingConventions callConvention,
	Type[] types,
	ParameterModifier[] modifiers
)
public final MethodInfo GetMethod (
	String name, 
	BindingFlags bindingAttr, 
	Binder binder, 
	CallingConventions callConvention, 
	Type[] types, 
	ParameterModifier[] modifiers
)
public final function GetMethod (
	name : String, 
	bindingAttr : BindingFlags, 
	binder : Binder, 
	callConvention : CallingConventions, 
	types : Type[], 
	modifiers : ParameterModifier[]
) : MethodInfo
Not applicable.

Parameters

name

The String containing the name of the method to get.

bindingAttr

A bitmask comprised of one or more BindingFlags that specify how the search is conducted.

-or-

Zero, to return a null reference (Nothing in Visual Basic).

binder

A Binder object that defines a set of properties and enables binding, which can involve selection of an overloaded method, coercion of argument types, and invocation of a member through reflection.

-or-

a null reference (Nothing in Visual Basic), to use the DefaultBinder.

callConvention

The CallingConventions object that specifies the set of rules to use regarding the order and layout of arguments, how the return value is passed, what registers are used for arguments, and how the stack is cleaned up.

types

An array of Type objects representing the number, order, and type of the parameters for the method to get.

-or-

An empty array of Type objects (as provided by the EmptyTypes field) to get a method that takes no parameters.

modifiers

An array of ParameterModifier objects representing the attributes associated with the corresponding element in the types array. To be only used when calling through COM interop, and only parameters that are passed by reference are handled. The default binder does not process this parameter.

Return Value

A MethodInfo object representing the method that matches the specified requirements, if found; otherwise, a null reference (Nothing in Visual Basic).
Exception typeCondition

AmbiguousMatchException

More than one method is found with the specified name and matching the specified binding constraints.

ArgumentNullException

name is a null reference (Nothing in Visual Basic).

-or-

types is a null reference (Nothing in Visual Basic).

-or-

One of the elements in types is a null reference (Nothing in Visual Basic).

ArgumentException

types is multidimensional.

-or-

modifiers is multidimensional.

Although the default binder does not process ParameterModifier (the modifiers parameter), you can use the abstract System.Reflection.Binder class to write a custom binder that does process modifiers. ParameterModifier is only used when calling through COM interop, and only parameters that are passed by reference are handled.

The following table shows what members of a base class are returned by the GetXXX methods when reflecting on a type.

Member Type

Static

Non-Static

Constructor

No

No

Field

No

Yes. A field is always hide-by-name-and-signature.

Event

Not applicable

The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.

Method

No

Yes. A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature.

Nested Type

No

No

Property

Not applicable

The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.

  1. Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.

  2. For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.

  3. Custom attributes are not part of the common type system.

The types array and the modifiers array have the same length. A parameter specified in the types array can have the following attributes, which are specified in the modifiers array: pdIn, pdOut, pdLcid, pdRetval, pdOptional, and pdHasDefault, which represent [In], [Out], [lcid], [retval], [optional], and a value specifying whether the parameter has a default value. A parameter's associated attributes are stored in the metadata and enhance interoperability.

The following BindingFlags filter flags can be used to define which methods to include in the search:

  • You must specify either BindingFlags.Instance or BindingFlags.Static in order to get a return.

  • Specify BindingFlags.Public to include public methods in the search.

  • Specify BindingFlags.NonPublic to include nonpublic methods (that is, private and protected members) in the search.

  • Specify BindingFlags.FlattenHierarchy to include public and protected static members up the hierarchy; private static members in inherited classes are not included.

The following BindingFlags modifier flags can be used to change how the search works:

  • BindingFlags.IgnoreCase to ignore the case of name.

  • BindingFlags.DeclaredOnly to search only the methods declared on the Type, not methods that were simply inherited.

See System.Reflection.BindingFlags for more information.

If the requested method is nonpublic and the caller does not have ReflectionPermission to reflect nonpublic objects outside the current assembly, this method returns a null reference (Nothing in Visual Basic).

NoteNote:

You cannot omit parameters when looking up constructors and methods. You can only omit parameters when invoking.

If the current T:System.Type represents a constructed generic type, this method returns the MethodInfo with the type parameters replaced by the appropriate type arguments.

If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the methods of the class constraint, or the methods of Object if there is no class constraint.

NoteNote:

For generic methods, do not include the type arguments in name. For example, the C# code GetMember("MyMethod<int>") searches for a member with the text name "MyMethod<int>", rather than for a method named MyMethod that has one generic argument of type int.

The following example finds specific overloads of MethodA, specifying binding constraints, calling conventions, and a variety of argument types.

NoteNote:

The Visual C# 2005 example requires the /unsafe compiler option.


using System;
using System.Reflection;

class Program
{
    // Methods to get:

    public void MethodA(int i, int j) { }

    public void MethodA(int[] i) { }

    public unsafe void MethodA(int* i) { }

    public void MethodA(ref int r) {}

    // Method that takes an out parameter:
    public void MethodA(int i, out int o) { o = 100;}


  static void Main(string[] args)
  {
    MethodInfo mInfo;

    // Get MethodA(int i, int j)
    mInfo = typeof(Program).GetMethod("MethodA",
        BindingFlags.Public | BindingFlags.Instance,
        null,
        CallingConventions.Any,
        new Type[] { typeof(int), typeof(int) },
        null);
    Console.WriteLine("Found method: {0}", mInfo);

    // Get MethodA(int[] i)
    mInfo = typeof(Program).GetMethod("MethodA",
        BindingFlags.Public | BindingFlags.Instance,
        null,
        CallingConventions.Any,
        new Type[] { typeof(int[]) },
        null);
    Console.WriteLine("Found method: {0}", mInfo);

    // Get MethodA(int* i)
    mInfo = typeof(Program).GetMethod("MethodA",
        BindingFlags.Public | BindingFlags.Instance,
        null,
        CallingConventions.Any,
        new Type[] { typeof(int).MakePointerType() },
        null);
    Console.WriteLine("Found method: {0}", mInfo);

    // Get MethodA(ref int r)
    mInfo = typeof(Program).GetMethod("MethodA",
        BindingFlags.Public | BindingFlags.Instance,
        null,
        CallingConventions.Any,
        new Type[] { typeof(int).MakeByRefType() },
        null);
    Console.WriteLine("Found method: {0}", mInfo);

    // Get MethodA(int i, out int o)
    mInfo = typeof(Program).GetMethod("MethodA",
        BindingFlags.Public | BindingFlags.Instance,
        null,
        CallingConventions.Any,
        new Type[] { typeof(int), typeof(int).MakeByRefType() },
        null);
    Console.WriteLine("Found method: {0}", mInfo);

  }
}


import System.*;
import System.Reflection.*;

public class Program
{
	// Methods to get:

	public void MethodA(int i, int j) { }

	public void MethodA(int[] i) { }

    public static void main(String[] args)
    {
		MethodInfo mInfo;
		Type tProgram = Program.class.ToType();


		// Get MethodA(int i, int j)
		mInfo = tProgram.GetMethod("MethodA",
			BindingFlags.Public | BindingFlags.Instance,
			null,
			CallingConventions.Any,
			new Type[] { int.class.ToType(), int.class.ToType()},
			null);
		Console.WriteLine("Found method: {0}", mInfo);

		// Get MethodA(int[] i)
		mInfo = tProgram.GetMethod("MethodA",
			BindingFlags.Public | BindingFlags.Instance,
			null,
			CallingConventions.Any,
			new Type[] { int[].class.ToType() },
			null);
		Console.WriteLine("Found method: {0}", mInfo);

    }
}


Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0
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