MethodImplAttribute Class
 
System_CAPS_noteNote

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Specifies the details of how a method is implemented. This class cannot be inherited.

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

SystemObject
   SystemAttribute
    System.Runtime.CompilerServicesMethodImplAttribute

[SerializableAttribute]
[AttributeUsageAttribute(AttributeTargets.Constructor | AttributeTargets.Method, 
	Inherited = false)]
[ComVisibleAttribute(true)]
public sealed class MethodImplAttribute : Attribute
[SerializableAttribute]
[AttributeUsageAttribute(AttributeTargets::Constructor | AttributeTargets::Method, 
	Inherited = false)]
[ComVisibleAttribute(true)]
public ref class MethodImplAttribute sealed : Attribute
[<Sealed>]
[<SerializableAttribute>]
[<AttributeUsageAttribute(AttributeTargets.Constructor | AttributeTargets.Method,
    Inherited = false)>]
[<ComVisibleAttribute(true)>]
type MethodImplAttribute = 
    class
        inherit Attribute
    end
<SerializableAttribute>
<AttributeUsageAttribute(AttributeTargets.Constructor Or AttributeTargets.Method,
	Inherited := False)>
<ComVisibleAttribute(True)>
Public NotInheritable Class MethodImplAttribute
	Inherits Attribute
NameDescription
System_CAPS_pubmethod MethodImplAttribute

Initializes a new instance of the MethodImplAttribute class.

System_CAPS_pubmethod MethodImplAttribute

Initializes a new instance of the MethodImplAttribute class with the specified MethodImplOptions value.

System_CAPS_pubmethod MethodImplAttribute

Initializes a new instance of the MethodImplAttribute class with the specified MethodImplOptions value.

NameDescription
System_CAPS_pubproperty

When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)

System_CAPS_pubproperty

Gets the MethodImplOptions value describing the attributed method.

NameDescription
System_CAPS_pubmethod Equals

This API supports the product infrastructure and is not intended to be used directly from your code. Returns a value that indicates whether this instance is equal to a specified object.(Inherited from Attribute.)

System_CAPS_pubmethod GetHashCode

Returns the hash code for this instance.(Inherited from Attribute.)

System_CAPS_pubmethod GetType

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethod IsDefaultAttribute

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.)

System_CAPS_pubmethod Match

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.)

System_CAPS_pubmethod ToString

Returns a string that represents the current object.(Inherited from Object.)

NameDescription
System_CAPS_pubfield MethodCodeType

A MethodCodeType value indicating what kind of implementation is provided for this method.

NameDescription
System_CAPS_pubinterface System_CAPS_privmethod _AttributeGetIDsOfNames

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterface System_CAPS_privmethod _AttributeGetTypeInfo

Retrieves the type information for an object, which can be used to get the type information for an interface.(Inherited from Attribute.)

System_CAPS_pubinterface System_CAPS_privmethod _AttributeGetTypeInfoCount

Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from Attribute.)

System_CAPS_pubinterface System_CAPS_privmethod _AttributeInvoke

Provides access to properties and methods exposed by an object.(Inherited from Attribute.)

You can apply this attribute to methods or constructors.

This attribute lets you customize the configuration of the method or constructor to which it applies by supplying a MethodImplOptions value to its class constructor. The members of the MethodImplOptions enumeration correspond to bit fields in the CorMethodImpl metadata table. This means that information on the attribute cannot be retrieved at run time by calling the MemberInfoGetCustomAttributes method; instead, it is retrieved by calling either the MethodInfo.GetMethodImplementationFlags or the ConstructorInfo.GetMethodImplementationFlags method.

The following example applies the MethodImplAttribute to the GetCalendarName method to ensure that it is not inlined at run time by the just-in-time (JIT) compiler.

using System;
using System.Globalization;
using System.Runtime.CompilerServices;

public class Utility
{
   [MethodImplAttribute(MethodImplOptions.NoInlining)] 
   public static string GetCalendarName(Calendar cal)
   {
      return cal.ToString().Replace("System.Globalization.", "").
                 Replace("Calendar", "");
   }
}
Imports System.Globalization
Imports System.Runtime.CompilerServices

Public Class Utility
   <MethodImplAttribute(MethodImplOptions.NoInlining)>
   Public Shared Function GetCalendarName(cal As Calendar) As String
      Return cal.ToString().Replace("System.Globalization.", "").Replace("Calendar", "")
   End Function
End Class

The following example then calls the MethodInfo.GetMethodImplementationFlags method to determine which flags are set for the GetCalendarName method. It also demonstrates that this information is not retrieved by the MemberInfoGetCustomAttributes method.

using System;
using System.Reflection;

public class Example
{
   public static void Main()
   {
      // Use reflection to get a reference to the GetCalendarName method.
      Assembly assem = Assembly.LoadFrom(@".\Example.dll");
      Type type = assem.GetType("Utility");
      MethodInfo methodInfo = type.GetMethod("GetCalendarName");

      // Determine whether the method has any custom attributes.
      Console.Write("Utility.GetCalendarName custom attributes:");
      object[] attribs = methodInfo.GetCustomAttributes(false);
      if (attribs.Length > 0) {
         Console.WriteLine();
         foreach (var attrib in attribs)
            Console.WriteLine("   " + attrib.ToString());   

      }
      else {
         Console.WriteLine("   <None>");
      }

      // Get the method's metadata flags.
      MethodImplAttributes flags = methodInfo.GetMethodImplementationFlags();
      Console.WriteLine("Utility.GetCalendarName flags: {0}", 
                        flags.ToString());      
   }
}
// The example displays the following output:
//     Utility.GetCalendarName custom attributes:   <None>
//     Utility.GetCalendarName flags: NoInlining
Imports System.Reflection

Module Example
   Public Sub Main()
      ' Use reflection to get a reference to the GetCalendarName method.
      Dim assem As Assembly = Assembly.LoadFrom(".\Example.dll")
      Dim type As Type = assem.GetType("Utility")
      Dim methodInfo As MethodInfo = type.GetMethod("GetCalendarName")

      ' Determine whether the method has any custom attributes.
      Console.Write("Utility.GetCalendarName custom attributes:")
      Dim attribs() As Object = methodInfo.GetCustomAttributes(False)
      If attribs.Length > 0 Then
         Console.WriteLine()
         For Each attrib As Object In attribs
            Console.WriteLine("   " + attrib.ToString())   
         Next
      Else
         Console.WriteLine("   <None>")
      End If

      ' Get the method's metadata flags.
      Dim flags As MethodImplAttributes = methodInfo.GetMethodImplementationFlags()
      Console.WriteLine("Utility.GetCalendarName flags: {0}", flags.ToString())      
   End Sub
End Module
' The example displays the following output:
'     Utility.GetCalendarName custom attributes:   <None>
'     Utility.GetCalendarName flags: NoInlining
Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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