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PropertyInfo Class

Discovers the attributes of a property and provides access to property metadata.

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

'Declaration
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
<ClassInterfaceAttribute(ClassInterfaceType.None)> _
<PermissionSetAttribute(SecurityAction.InheritanceDemand, Name := "FullTrust")> _
Public MustInherit Class PropertyInfo _
	Inherits MemberInfo _
	Implements _PropertyInfo
'Usage
Dim instance As PropertyInfo

Properties are logically the same as fields. A property is a named aspect of an object's state whose value is typically accessible through get and set accessors. Properties may be read-only, in which case a set routine is not supported.

NoteNote:

To determine whether a property is static, you must obtain the MethodInfo for the get or set accessor, by calling the GetGetMethod or the GetSetMethod method, and examine its IsStatic property.

Several methods in this class assume that the get accessor and set accessor methods of a property have certain formats. The signatures of the get and set methods must match the following convention:

  • The return type of the get method and the last argument of the set method must be identical. This is the type of the property.

  • The get and set methods must have the same number, type, and order of indices.

If this format is not followed, the behavior of the GetValue and SetValue methods is undefined.

Calling ICustomAttributeProvider.GetCustomAttributes on PropertyInfo when the inherit parameter of GetCustomAttributes is true does not walk the type hierarchy. Use System.Attribute to inherit custom attributes.

Notes to Inheritors:

When you inherit from PropertyInfo, you must override the following members: GetValue, SetValue, GetAccessors, GetGetMethod, GetSetMethod, and GetIndexParameters.

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

NoteNote:

This example generates about 55,000 lines of data, which you can redirect to a text file at the command prompt, as follows: example.exe > propertyinfo.txt

Imports System
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] = System.Reflection.Assembly.GetExecutingAssembly()
        Display(indent, "Assembly identity={0}", a.FullName)
        Display(indent + 1, "Codebase={0}", a.CodeBase)

        ' Display the set of assemblies our assemblies references. 
        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() 
'

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

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