Bagikan melalui


Type.GetMember Method (String)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Searches for the public members with the specified name.

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

Syntax

'Declaration
Public Function GetMember ( _
    name As String _
) As MemberInfo()
public MemberInfo[] GetMember(
    string name
)

Parameters

Return Value

Type: array<System.Reflection.MemberInfo[]
An array of MemberInfo objects representing the public members with the specified name, if found; otherwise, an empty array.

Exceptions

Exception Condition
ArgumentNullException

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

Remarks

The search for name is case-sensitive. The search includes public static and public instance members.

Members include properties, methods, fields, events, and so on.

The GetMember method does not return members in a particular order, such as alphabetical or declaration order. Your code must not depend on the order in which members are returned, because that order varies.

This method overload will not find class initializers (.cctor). To find class initializers, use an overload that takes BindingFlags, and specify BindingFlags.Static | BindingFlags.NonPublic (BindingFlags.StaticOrBindingFlags.NonPublic in Visual Basic).

The following table shows what members of a base class are returned by the Get 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.

Notes:

  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.

If the current Type represents a constructed generic type, this method returns the MemberInfo 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 members of the class constraint, or the members 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.

Platform Notes

Silverlight for Windows Phone Silverlight for Windows Phone

 GetMember does not return any public members with the specified name if the name string is a regular expression.

Examples

The following example displays all the members of the String class demonstrates all three overloads of the GetMember method.


Imports System.Security
Imports System.Reflection

Public Class Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim [myClass] As New Example()
      Try
         [myClass].GetMemberInfo(outputBlock)
         [myClass].GetPublicStaticMemberInfo(outputBlock)
         [myClass].GetPublicInstanceMethodMemberInfo(outputBlock)
      Catch e As ArgumentNullException
         outputBlock.Text &= "ArgumentNullException occurred." & vbCrLf
         outputBlock.Text &= ("Message: " + e.Message) & vbCrLf
      Catch e As NotSupportedException
         outputBlock.Text &= "NotSupportedException occurred." & vbCrLf
         outputBlock.Text &= ("Message: " + e.Message) & vbCrLf
      Catch e As SecurityException
         outputBlock.Text &= "SecurityException occurred." & vbCrLf
         outputBlock.Text &= ("Message: " + e.Message) & vbCrLf
      Catch e As Exception
         outputBlock.Text &= "Exception occurred." & vbCrLf
         outputBlock.Text &= ("Message: " + e.Message) & vbCrLf
      End Try
   End Sub 'Main


   Public Sub GetMemberInfo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim myString As [String] = "GetMember_String"
      Dim myType As Type = myString.GetType()
      ' Get the members for myString starting with the letter C.
      Dim myMembers As MemberInfo() = myType.GetMember("C*")
      If myMembers.Length > 0 Then
         outputBlock.Text += String.Format(ControlChars.Cr + "The member(s) starting with the letter C for type {0}:", myType) & vbCrLf
         Dim index As Integer
         For index = 0 To myMembers.Length - 1
            outputBlock.Text += String.Format("Member {0}: {1}", index + 1, myMembers(index).ToString()) & vbCrLf
         Next index
      Else
         outputBlock.Text &= "No members match the search criteria." & vbCrLf
      End If
   End Sub 'GetMemberInfo

   Public Sub GetPublicStaticMemberInfo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim myString As [String] = "GetMember_String_BindingFlag"

      Dim myType As Type = myString.GetType()
      ' Get the public static members for the class myString starting with the letter C.
      Dim myMembers As MemberInfo() = myType.GetMember("C*", BindingFlags.Public Or BindingFlags.Static)

      If myMembers.Length > 0 Then
         outputBlock.Text += String.Format(ControlChars.Cr + "The public static member(s) starting with the letter C for type {0}:", myType) & vbCrLf
         Dim index As Integer
         For index = 0 To myMembers.Length - 1
            outputBlock.Text += String.Format("Member {0}: {1}", index + 1, myMembers(index).ToString()) & vbCrLf
         Next index
      Else
         outputBlock.Text &= "No members match the search criteria." & vbCrLf
      End If
   End Sub 'GetPublicStaticMemberInfo

   Public Sub GetPublicInstanceMethodMemberInfo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim myString As [String] = "GetMember_String_MemberType_BindingFlag"

      Dim myType As Type = myString.GetType()
      ' Get the public instance methods for myString starting with the letter C.
      Dim myMembers As MemberInfo() = myType.GetMember("C*", MemberTypes.Method, BindingFlags.Public Or BindingFlags.Instance)
      If myMembers.Length > 0 Then
         outputBlock.Text += String.Format(ControlChars.Cr + "The public instance method(s) starting with the letter C for type {0}:", myType) & vbCrLf
         Dim index As Integer
         For index = 0 To myMembers.Length - 1
            outputBlock.Text += String.Format("Member {0}: {1}", index + 1, myMembers(index).ToString()) & vbCrLf
         Next index
      Else
         outputBlock.Text &= "No members match the search criteria." & vbCrLf
      End If
   End Sub 'GetPublicInstanceMethodMemberInfo 
End Class 'MyMemberSample

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

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      Example myClass = new Example();
      try
      {
         myClass.GetMemberInfo(outputBlock);
         myClass.GetPublicStaticMemberInfo(outputBlock);
         myClass.GetPublicInstanceMethodMemberInfo(outputBlock);
      }
      catch (ArgumentNullException e)
      {
         outputBlock.Text += "ArgumentNullException occurred." + "\n";
         outputBlock.Text += "Message: " + e.Message + "\n";
      }
      catch (NotSupportedException e)
      {
         outputBlock.Text += "NotSupportedException occurred." + "\n";
         outputBlock.Text += "Message: " + e.Message + "\n";
      }
      catch (SecurityException e)
      {
         outputBlock.Text += "SecurityException occurred." + "\n";
         outputBlock.Text += "Message: " + e.Message + "\n";
      }
      catch (Exception e)
      {
         outputBlock.Text += "Exception occurred." + "\n";
         outputBlock.Text += "Message: " + e.Message + "\n";
      }
   }

   public void GetMemberInfo(System.Windows.Controls.TextBlock outputBlock)
   {
      String myString = "GetMember_String";

      Type myType = myString.GetType();
      // Get the members for myString starting with the letter C.
      MemberInfo[] myMembers = myType.GetMember("C*");
      if (myMembers.Length > 0)
      {
         outputBlock.Text += String.Format("\nThe member(s) starting with the letter C for type {0}:", myType) + "\n";
         for (int index = 0; index < myMembers.Length; index++)
            outputBlock.Text += String.Format("Member {0}: {1}", index + 1, myMembers[index].ToString()) + "\n";
      }
      else
         outputBlock.Text += "No members match the search criteria." + "\n";
   }

   public void GetPublicStaticMemberInfo(System.Windows.Controls.TextBlock outputBlock)
   {
      String myString = "GetMember_String_BindingFlag";
      Type myType = myString.GetType();
      // Get the public static members for the class myString starting with the letter C.
      MemberInfo[] myMembers = myType.GetMember("C*",
          BindingFlags.Public | BindingFlags.Static);
      if (myMembers.Length > 0)
      {
         outputBlock.Text += String.Format("\nThe public static member(s) starting with the letter C for type {0}:", myType) + "\n";
         for (int index = 0; index < myMembers.Length; index++)
            outputBlock.Text += String.Format("Member {0}: {1}", index + 1, myMembers[index].ToString()) + "\n";
      }
      else
         outputBlock.Text += "No members match the search criteria." + "\n";
   }

   public void GetPublicInstanceMethodMemberInfo(System.Windows.Controls.TextBlock outputBlock)
   {
      String myString = "GetMember_String_MemberType_BindingFlag";
      Type myType = myString.GetType();
      // Get the public instance methods for myString starting with the letter C.
      MemberInfo[] myMembers = myType.GetMember("C*", MemberTypes.Method,
          BindingFlags.Public | BindingFlags.Instance);
      if (myMembers.Length > 0)
      {
         outputBlock.Text += String.Format("\nThe public instance method(s) starting with the letter C for type {0}:", myType) + "\n";
         for (int index = 0; index < myMembers.Length; index++)
            outputBlock.Text += String.Format("Member {0}: {1}", index + 1, myMembers[index].ToString()) + "\n";
      }
      else
         outputBlock.Text += "No members match the search criteria." + "\n";
   }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.