MemberInfo Class

Definition

Namespace:

System.Reflection

Assembly:

System.Runtime.dll

Source:

MemberInfo.cs

Obtains information about the attributes of a member and provides access to member metadata.

public ref class MemberInfo abstract : System::Reflection::ICustomAttributeProvider

public abstract class MemberInfo : System.Reflection.ICustomAttributeProvider

type MemberInfo = class
    interface ICustomAttributeProvider

Public MustInherit Class MemberInfo
Implements ICustomAttributeProvider

Inheritance

Object

MemberInfo

Derived

System.Reflection.EventInfo

System.Reflection.FieldInfo

System.Reflection.MethodBase

System.Reflection.PropertyInfo

System.Type

Implements

ICustomAttributeProvider

Examples

This example shows how to use various reflection classes to analyze the metadata contained in an assembly.

using namespace System;
using namespace System::Reflection;

static void Display(Int32 indent, String^ format, ... array<Object^>^param) 
{
    Console::Write("{0}", gcnew String (' ', indent));
    Console::WriteLine(format, param);
}
    
// Displays the custom attributes applied to the specified member.
static void DisplayAttributes(Int32 indent, MemberInfo^ mi)
{
    // Get the set of custom attributes; if none exist, just return.
    array<Object^>^attrs = mi->GetCustomAttributes(false);
        
    if (attrs->Length==0)
    {
        return;          
    }
        
    // Display the custom attributes applied to this member.
    Display(indent+1, "Attributes:");
    for each ( Object^ o in attrs )
    {
        Display(indent*2, "{0}", o);
    }				
}

void main()
{
    try
    {
        // This variable holds the amount of indenting that 
        // should be used when displaying each line of information.
        Int32 indent = 0; 
        // Display information about the EXE assembly.
        Assembly^ a = System::Reflection::Assembly::GetExecutingAssembly();
        
        Display(indent, "Assembly identity={0}", gcnew array<Object^> {a->FullName});
        Display(indent+1, "Codebase={0}", gcnew array<Object^> {a->CodeBase});

        // Display the set of assemblies our assemblies reference.
  
        Display(indent, "Referenced assemblies:"); 

        for each ( AssemblyName^ an in a->GetReferencedAssemblies() )
        {
            Display(indent + 1, "Name={0}, Version={1}, Culture={2}, PublicKey token={3}", gcnew array<Object^> {an->Name, an->Version, an->CultureInfo, (BitConverter::ToString(an->GetPublicKeyToken()))});
        }
        Display(indent, "");  
        // Display information about each assembly loading into this AppDomain. 
        for each ( Assembly^ b in AppDomain::CurrentDomain->GetAssemblies()) 
        {
            Display(indent, "Assembly: {0}", gcnew array<Object^> {b});
            // Display information about each module of this assembly.
 
            for each ( Module^ m in b->GetModules(true) ) 
            {
                Display(indent+1, "Module: {0}", gcnew array<Object^> {m->Name});
            }
            // Display information about each type exported from this assembly.
           
            indent += 1; 
            for each ( Type^ t in b->GetExportedTypes() ) 
            {
                Display(0, "");  
                Display(indent, "Type: {0}", gcnew array<Object^> {t}); 

                // For each type, show its members & their custom attributes.
           
                indent += 1; 
                for each (MemberInfo^ mi in t->GetMembers() )
                {
                    Display(indent, "Member: {0}", gcnew array<Object^> {mi->Name}); 
                    DisplayAttributes(indent, mi);

                    // If the member is a method, display information about its parameters.         
                    if (mi->MemberType==MemberTypes::Method) 
                    {
                    
                        for each ( ParameterInfo^ pi in (((MethodInfo^) mi)->GetParameters()))
                        {
                            Display(indent+1, "Parameter: Type={0}, Name={1}", gcnew array<Object^> {pi->ParameterType, pi->Name}); 
                        }
                    }

                    // If the member is a property, display information about the property's accessor methods.
                    if (mi->MemberType==MemberTypes::Property) 
                    {
                        for each ( MethodInfo^ am in (((PropertyInfo^) mi)->GetAccessors()) )
                        {
                            Display(indent+1, "Accessor method: {0}", gcnew array<Object^> {am});
                        }
                    }
                }
                // Display a formatted string indented by the specified amount.               
                indent -= 1;
            }
            indent -= 1;
        }
    }
    catch (Exception^ e)
    {
        Console::WriteLine(e->Message);
    }
}

// The output shown below is abbreviated.
//
//Assembly identity=Reflection, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
//  Codebase=file:///C:/Reflection.exe
//Referenced assemblies:
//  Name=mscorlib, Version=1.0.5000.0, Culture=, PublicKey token=B7-7A-5C-56-19-34-E0-89
//  Name=Microsoft.VisualBasic, Version=7.0.5000.0, Culture=, PublicKey token=B0-3F-5F-7F-11-D5-0A-3A
//
//Assembly: mscorlib, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
//  Module: mscorlib.dll
//  Module: prc.nlp
//  Module: prcp.nlp
//  Module: ksc.nlp
//  Module: ctype.nlp
//  Module: xjis.nlp
//  Module: bopomofo.nlp
//  Module: culture.nlp
//  Module: region.nlp
//  Module: sortkey.nlp
//  Module: charinfo.nlp
//  Module: big5.nlp
//  Module: sorttbls.nlp
//  Module: l_intl.nlp
//  Module: l_except.nlp
//
//  Type: System.Object
//    Member: GetHashCode
//    Member: Equals
//      Parameter: Type=System.Object, Name=obj
//    Member: ToString
//    Member: Equals
//      Parameter: Type=System.Object, Name=objA
//      Parameter: Type=System.Object, Name=objB
//    Member: ReferenceEquals
//      Parameter: Type=System.Object, Name=objA
//      Parameter: Type=System.Object, Name=objB
//    Member: GetType
//    Member: .ctor
//
//  Type: System.ICloneable
//    Member: Clone
//
//  Type: System.Collections.IEnumerable
//    Member: GetEnumerator
//      Attributes:
//        System.Runtime.InteropServices.DispIdAttribute
//
//  Type: System.Collections.ICollection
//    Member: get_IsSynchronized
//    Member: get_SyncRoot
//    Member: get_Count
//    Member: CopyTo
//      Parameter: Type=System.Array, Name=array
//      Parameter: Type=System.Int32, Name=index
//    Member: Count
//      Accessor method: Int32 get_Count()
//    Member: SyncRoot
//      Accessor method: System.Object get_SyncRoot()
//    Member: IsSynchronized
//      Accessor method: Boolean get_IsSynchronized()
//

using System;
using System.Reflection;

class Module1
{
    public static void Main()
    {
        // This variable holds the amount of indenting that
        // should be used when displaying each line of information.
        Int32 indent = 0;
        // Display information about the EXE assembly.
        Assembly a = typeof(Module1).Assembly;
        Display(indent, "Assembly identity={0}", a.FullName);
        Display(indent+1, "Codebase={0}", a.CodeBase);

        // Display the set of assemblies our assemblies reference.

        Display(indent, "Referenced assemblies:");
        foreach (AssemblyName an in a.GetReferencedAssemblies() )
        {
             Display(indent + 1, "Name={0}, Version={1}, Culture={2}, PublicKey token={3}", an.Name, an.Version, an.CultureInfo.Name, (BitConverter.ToString (an.GetPublicKeyToken())));
        }
        Display(indent, "");

        // Display information about each assembly loading into this AppDomain.
        foreach (Assembly b in AppDomain.CurrentDomain.GetAssemblies())
        {
            Display(indent, "Assembly: {0}", b);

            // Display information about each module of this assembly.
            foreach ( Module m in b.GetModules(true) )
            {
                Display(indent+1, "Module: {0}", m.Name);
            }

            // Display information about each type exported from this assembly.

            indent += 1;
            foreach ( Type t in b.GetExportedTypes() )
            {
                Display(0, "");
                Display(indent, "Type: {0}", t);

                // For each type, show its members & their custom attributes.

                indent += 1;
                foreach (MemberInfo mi in t.GetMembers() )
                {
                    Display(indent, "Member: {0}", mi.Name);
                    DisplayAttributes(indent, mi);

                    // If the member is a method, display information about its parameters.

                    if (mi.MemberType==MemberTypes.Method)
                    {
                        foreach ( ParameterInfo pi in ((MethodInfo) mi).GetParameters() )
                        {
                            Display(indent+1, "Parameter: Type={0}, Name={1}", pi.ParameterType, pi.Name);
                        }
                    }

                    // If the member is a property, display information about the property's accessor methods.
                    if (mi.MemberType==MemberTypes.Property)
                    {
                        foreach ( MethodInfo am in ((PropertyInfo) mi).GetAccessors() )
                        {
                            Display(indent+1, "Accessor method: {0}", am);
                        }
                    }
                }
                indent -= 1;
            }
            indent -= 1;
        }
    }

    // Displays the custom attributes applied to the specified member.
    public static void DisplayAttributes(Int32 indent, MemberInfo mi)
    {
        // Get the set of custom attributes; if none exist, just return.
        object[] attrs = mi.GetCustomAttributes(false);
        if (attrs.Length==0) {return;}

        // Display the custom attributes applied to this member.
        Display(indent+1, "Attributes:");
        foreach ( object o in attrs )
        {
            Display(indent+2, "{0}", o.ToString());
        }
    }

    // Display a formatted string indented by the specified amount.
    public static void Display(Int32 indent, string format, params object[] param)

    {
        Console.Write(new string(' ', indent*2));
        Console.WriteLine(format, param);
    }
}

//The output shown below is abbreviated.
//
//Assembly identity=ReflectionCS, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null
//  Codebase=file:///C:/Documents and Settings/test/My Documents/Visual Studio 2005/Projects/Reflection/Reflection/obj/Debug/Reflection.exe
//Referenced assemblies:
//  Name=mscorlib, Version=2.0.0.0, Culture=, PublicKey token=B7-7A-5C-56-19-34-E0-89
//
//Assembly: mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//  Module: mscorlib.dll
//
//  Type: System.Object
//    Member: GetType
//    Member: ToString
//    Member: Equals
//      Parameter: Type=System.Object, Name=obj
//    Member: Equals
//      Parameter: Type=System.Object, Name=objA
//      Parameter: Type=System.Object, Name=objB
//    Member: ReferenceEquals
//      Attributes:
//        System.Runtime.ConstrainedExecution.ReliabilityContractAttribute
//      Parameter: Type=System.Object, Name=objA
//      Parameter: Type=System.Object, Name=objB
//    Member: GetHashCode
//    Member: .ctor
//      Attributes:
//        System.Runtime.ConstrainedExecution.ReliabilityContractAttribute
//
//  Type: System.ICloneable
//    Member: Clone
//
//  Type: System.Collections.IEnumerable
//    Member: GetEnumerator
//      Attributes:
//        System.Runtime.InteropServices.DispIdAttribute
//
//  Type: System.Collections.ICollection
//    Member: CopyTo
//      Parameter: Type=System.Array, Name=array
//      Parameter: Type=System.Int32, Name=index
//    Member: get_Count
//    Member: get_SyncRoot
//    Member: get_IsSynchronized
//    Member: Count
//      Accessor method: Int32 get_Count()
//    Member: SyncRoot
//      Accessor method: System.Object get_SyncRoot()
//    Member: IsSynchronized
//      Accessor method: Boolean get_IsSynchronized()
//
//  Type: System.Collections.IList
//    Member: get_Item
//      Parameter: Type=System.Int32, Name=index
//    Member: set_Item
//      Parameter: Type=System.Int32, Name=index
//      Parameter: Type=System.Object, Name=value
//    Member: Add
//      Parameter: Type=System.Object, Name=value
//    Member: Contains
//      Parameter: Type=System.Object, Name=value
//    Member: Clear
//    Member: get_IsReadOnly
//    Member: get_IsFixedSize
//    Member: IndexOf
//      Parameter: Type=System.Object, Name=value
//    Member: Insert
//      Parameter: Type=System.Int32, Name=index
//      Parameter: Type=System.Object, Name=value
//    Member: Remove
//      Parameter: Type=System.Object, Name=value
//    Member: RemoveAt
//      Parameter: Type=System.Int32, Name=index
//    Member: Item
//      Accessor method: System.Object get_Item(Int32)
//      Accessor method: Void set_Item(Int32, System.Object)
//    Member: IsReadOnly
//      Accessor method: Boolean get_IsReadOnly()
//    Member: IsFixedSize
//      Accessor method: Boolean get_IsFixedSize()
//
//  Type: System.Array
//    Member: IndexOf
//      Parameter: Type=T[], Name=array
//      Parameter: Type=T, Name=value
//    Member: AsReadOnly
//      Parameter: Type=T[], Name=array
//    Member: Resize
//      Attributes:
//        System.Runtime.ConstrainedExecution.ReliabilityContractAttribute
//      Parameter: Type=T[]&, Name=array
//      Parameter: Type=System.Int32, Name=newSize
//    Member: BinarySearch
//      Attributes:
//        System.Runtime.ConstrainedExecution.ReliabilityContractAttribute
//      Parameter: Type=T[], Name=array
//      Parameter: Type=T, Name=value
//    Member: BinarySearch
//      Attributes:
//        System.Runtime.ConstrainedExecution.ReliabilityContractAttribute
//      Parameter: Type=T[], Name=array
//      Parameter: Type=T, Name=value
//      Parameter: Type=System.Collections.Generic.IComparer`1[T], Name=comparer

Imports System.Reflection

Module Module1
    Sub Main()
        ' This variable holds the amount of indenting that 
        ' should be used when displaying each line of information.
        Dim indent As Int32 = 0
        ' Display information about the EXE assembly.
        Dim a As Assembly = GetType(Module1).Assembly
        Display(indent, "Assembly identity={0}", a.FullName)
        Display(indent + 1, "Codebase={0}", a.CodeBase)

        ' Display the set of assemblies our assemblies reference.
        Dim an As AssemblyName
        Display(indent, "Referenced assemblies:")
        For Each an In a.GetReferencedAssemblies()
            Display(indent + 1, "Name={0}, Version={1}, Culture={2}, PublicKey token={3}", _
                an.Name, an.Version, an.CultureInfo.Name, BitConverter.ToString(an.GetPublicKeyToken))
        Next
        Display(indent, "")

        ' Display information about each assembly loading into this AppDomain.
        For Each a In AppDomain.CurrentDomain.GetAssemblies()
            Display(indent, "Assembly: {0}", a)

            ' Display information about each module of this assembly.
            Dim m As [Module]
            For Each m In a.GetModules(True)
                Display(indent + 1, "Module: {0}", m.Name)
            Next

            ' Display information about each type exported from this assembly.
            Dim t As Type
            indent += 1
            For Each t In a.GetExportedTypes()
                Display(0, "")
                Display(indent, "Type: {0}", t)

                ' For each type, show its members & their custom attributes.
                Dim mi As MemberInfo
                indent += 1
                For Each mi In t.GetMembers()
                    Display(indent, "Member: {0}", mi.Name)
                    DisplayAttributes(indent, mi)

                    ' If the member is a method, display information about its parameters.
                    Dim pi As ParameterInfo
                    If mi.MemberType = MemberTypes.Method Then
                        For Each pi In CType(mi, MethodInfo).GetParameters()
                            Display(indent + 1, "Parameter: Type={0}, Name={1}", pi.ParameterType, pi.Name)
                        Next
                    End If

                    ' If the member is a property, display information about the property's accessor methods.
                    If mi.MemberType = MemberTypes.Property Then
                        Dim am As MethodInfo
                        For Each am In CType(mi, PropertyInfo).GetAccessors()
                            Display(indent + 1, "Accessor method: {0}", am)
                        Next
                    End If
                Next
                indent -= 1
            Next
            indent -= 1
        Next
    End Sub

    ' Displays the custom attributes applied to the specified member.
    Sub DisplayAttributes(ByVal indent As Int32, ByVal mi As MemberInfo)
        ' Get the set of custom attributes; if none exist, just return.
        Dim attrs() As Object = mi.GetCustomAttributes(False)
        If attrs.Length = 0 Then Return

        ' Display the custom attributes applied to this member.
        Display(indent + 1, "Attributes:")
        Dim o As Object
        For Each o In attrs
            Display(indent + 2, "{0}", o.ToString())
        Next
    End Sub

    ' Display a formatted string indented by the specified amount.
    Sub Display(ByVal indent As Int32, ByVal format As String, ByVal ParamArray params() As Object)
        Console.Write(New String(" "c, indent * 2))
        Console.WriteLine(format, params)
    End Sub
End Module

'The output shown below is abbreviated.
'
'Assembly identity=Reflection, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
'  Codebase=file:///C:/Reflection.exe
'Referenced assemblies:
'  Name=mscorlib, Version=1.0.5000.0, Culture=, PublicKey token=B7-7A-5C-56-19-34-E0-89
'  Name=Microsoft.VisualBasic, Version=7.0.5000.0, Culture=, PublicKey token=B0-3F-5F-7F-11-D5-0A-3A
'
'Assembly: mscorlib, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089
'  Module: mscorlib.dll
'  Module: prc.nlp
'  Module: prcp.nlp
'  Module: ksc.nlp
'  Module: ctype.nlp
'  Module: xjis.nlp
'  Module: bopomofo.nlp
'  Module: culture.nlp
'  Module: region.nlp
'  Module: sortkey.nlp
'  Module: charinfo.nlp
'  Module: big5.nlp
'  Module: sorttbls.nlp
'  Module: l_intl.nlp
'  Module: l_except.nlp
'
'  Type: System.Object
'    Member: GetHashCode
'    Member: Equals
'      Parameter: Type=System.Object, Name=obj
'    Member: ToString
'    Member: Equals
'      Parameter: Type=System.Object, Name=objA
'      Parameter: Type=System.Object, Name=objB
'    Member: ReferenceEquals
'      Parameter: Type=System.Object, Name=objA
'      Parameter: Type=System.Object, Name=objB
'    Member: GetType
'    Member: .ctor
'
'  Type: System.ICloneable
'    Member: Clone
'
'  Type: System.Collections.IEnumerable
'    Member: GetEnumerator
'      Attributes:
'        System.Runtime.InteropServices.DispIdAttribute
'
'  Type: System.Collections.ICollection
'    Member: get_IsSynchronized
'    Member: get_SyncRoot
'    Member: get_Count
'    Member: CopyTo
'      Parameter: Type=System.Array, Name=array
'      Parameter: Type=System.Int32, Name=index
'    Member: Count
'      Accessor method: Int32 get_Count()
'    Member: SyncRoot
'      Accessor method: System.Object get_SyncRoot()
'    Member: IsSynchronized
'      Accessor method: Boolean get_IsSynchronized()
'

Remarks

The MemberInfo class is the abstract base class for classes used to obtain information about all members of a class (constructors, events, fields, methods, and properties).

This class introduces the basic functionality that all members provide.

Notes to Implementers

When you inherit from MemberInfo you must override the following members: GetCustomAttributes(Boolean) and IsDefined(Type, Boolean).

Constructors

MemberInfo()

Initializes a new instance of the MemberInfo class.

Properties

CustomAttributes	Gets a collection that contains this member's custom attributes.
DeclaringType	Gets the class that declares this member.
IsCollectible	Gets a value that indicates whether this MemberInfo object is part of an assembly held in a collectible AssemblyLoadContext.
MemberType	When overridden in a derived class, gets a MemberTypes value indicating the type of the member - method, constructor, event, and so on.
MetadataToken	Gets a value that identifies a metadata element.
Module	Gets the module in which the type that declares the member represented by the current MemberInfo is defined.
Name	Gets the name of the current member.
ReflectedType	Gets the class object that was used to obtain this instance of MemberInfo.

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object.
GetCustomAttributes(Boolean)	When overridden in a derived class, returns an array of all custom attributes applied to this member.
GetCustomAttributes(Type, Boolean)	When overridden in a derived class, returns an array of custom attributes applied to this member and identified by Type.
GetCustomAttributesData()	Returns a list of CustomAttributeData objects representing data about the attributes that have been applied to the target member.
GetHashCode()	Returns the hash code for this instance.
GetType()	Gets the Type of the current instance. (Inherited from Object)
HasSameMetadataDefinitionAs(MemberInfo)
IsDefined(Type, Boolean)	When overridden in a derived class, indicates whether one or more attributes of the specified type or of its derived types is applied to this member.
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Operators

Equality(MemberInfo, MemberInfo)	Indicates whether two MemberInfo objects are equal.
Inequality(MemberInfo, MemberInfo)	Indicates whether two MemberInfo objects are not equal.

Extension Methods

GetCustomAttribute(MemberInfo, Type, Boolean)	Retrieves a custom attribute of a specified type that is applied to a specified member, and optionally inspects the ancestors of that member.
GetCustomAttribute(MemberInfo, Type)	Retrieves a custom attribute of a specified type that is applied to a specified member.
GetCustomAttribute<T>(MemberInfo, Boolean)	Retrieves a custom attribute of a specified type that is applied to a specified member, and optionally inspects the ancestors of that member.
GetCustomAttribute<T>(MemberInfo)	Retrieves a custom attribute of a specified type that is applied to a specified member.
GetCustomAttributes(MemberInfo, Boolean)	Retrieves a collection of custom attributes that are applied to a specified member, and optionally inspects the ancestors of that member.
GetCustomAttributes(MemberInfo, Type, Boolean)	Retrieves a collection of custom attributes of a specified type that are applied to a specified member, and optionally inspects the ancestors of that member.
GetCustomAttributes(MemberInfo, Type)	Retrieves a collection of custom attributes of a specified type that are applied to a specified member.
GetCustomAttributes(MemberInfo)	Retrieves a collection of custom attributes that are applied to a specified member.
GetCustomAttributes<T>(MemberInfo, Boolean)	Retrieves a collection of custom attributes of a specified type that are applied to a specified member, and optionally inspects the ancestors of that member.
GetCustomAttributes<T>(MemberInfo)	Retrieves a collection of custom attributes of a specified type that are applied to a specified member.
IsDefined(MemberInfo, Type, Boolean)	Indicates whether custom attributes of a specified type are applied to a specified member, and, optionally, applied to its ancestors.
IsDefined(MemberInfo, Type)	Indicates whether custom attributes of a specified type are applied to a specified member.
GetMetadataToken(MemberInfo)	Gets a metadata token for the given member, if available.
HasMetadataToken(MemberInfo)	Returns a value that indicates whether a metadata token is available for the specified member.

Thread Safety

This type is thread safe.