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PropertyBuilder Class

Defines the properties for a type.

System.Object
  System.Reflection.MemberInfo
    System.Reflection.PropertyInfo
      System.Reflection.Emit.PropertyBuilder

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

'Declaration
<ComVisibleAttribute(True)> _
<ClassInterfaceAttribute(ClassInterfaceType.None)> _
<HostProtectionAttribute(SecurityAction.LinkDemand, MayLeakOnAbort := True)> _
Public NotInheritable Class PropertyBuilder _
	Inherits PropertyInfo _
	Implements _PropertyBuilder

The PropertyBuilder type exposes the following members.

  NameDescription
Public propertyAttributesGets the attributes for this property. (Overrides PropertyInfo.Attributes.)
Public propertyCanReadGets a value indicating whether the property can be read. (Overrides PropertyInfo.CanRead.)
Public propertyCanWriteGets a value indicating whether the property can be written to. (Overrides PropertyInfo.CanWrite.)
Public propertyDeclaringTypeGets the class that declares this member. (Overrides MemberInfo.DeclaringType.)
Public propertyIsSpecialNameGets a value indicating whether the property is the special name. (Inherited from PropertyInfo.)
Public propertyMemberTypeGets a MemberTypes value indicating that this member is a property. (Inherited from PropertyInfo.)
Public propertyMetadataTokenGets a value that identifies a metadata element. (Inherited from MemberInfo.)
Public propertyModuleGets the module in which the type that declares the current property is being defined. (Overrides MemberInfo.Module.)
Public propertyNameGets the name of this member. (Overrides MemberInfo.Name.)
Public propertyPropertyTokenRetrieves the token for this property.
Public propertyPropertyTypeGets the type of the field of this property. (Overrides PropertyInfo.PropertyType.)
Public propertyReflectedTypeGets the class object that was used to obtain this instance of MemberInfo. (Overrides MemberInfo.ReflectedType.)
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  NameDescription
Public methodAddOtherMethodAdds one of the other methods associated with this property.
Public methodEqualsReturns a value that indicates whether this instance is equal to a specified object. (Inherited from PropertyInfo.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetAccessorsReturns an array whose elements reflect the public get, set, and other accessors of the property reflected by the current instance. (Inherited from PropertyInfo.)
Public methodGetAccessors(Boolean)Returns an array of the public and non-public get and set accessors on this property. (Overrides PropertyInfo.GetAccessors(Boolean).)
Public methodGetConstantValueReturns a literal value associated with the property by a compiler. (Inherited from PropertyInfo.)
Public methodGetCustomAttributes(Boolean)Returns an array of all the custom attributes for this property. (Overrides MemberInfo.GetCustomAttributes(Boolean).)
Public methodGetCustomAttributes(Type, Boolean)Returns an array of custom attributes identified by Type. (Overrides MemberInfo.GetCustomAttributes(Type, Boolean).)
Public methodGetCustomAttributesDataReturns a list of CustomAttributeData objects representing data about the attributes that have been applied to the target member. (Inherited from MemberInfo.)
Public methodGetGetMethodReturns the public get accessor for this property. (Inherited from PropertyInfo.)
Public methodGetGetMethod(Boolean)Returns the public and non-public get accessor for this property. (Overrides PropertyInfo.GetGetMethod(Boolean).)
Public methodGetHashCodeReturns the hash code for this instance. (Inherited from PropertyInfo.)
Public methodGetIndexParametersReturns an array of all the index parameters for the property. (Overrides PropertyInfo.GetIndexParameters.)
Public methodGetOptionalCustomModifiersReturns an array of types representing the optional custom modifiers of the property. (Inherited from PropertyInfo.)
Public methodGetRawConstantValueReturns a literal value associated with the property by a compiler. (Inherited from PropertyInfo.)
Public methodGetRequiredCustomModifiersReturns an array of types representing the required custom modifiers of the property. (Inherited from PropertyInfo.)
Public methodGetSetMethodReturns the public set accessor for this property. (Inherited from PropertyInfo.)
Public methodGetSetMethod(Boolean)Returns the set accessor for this property. (Overrides PropertyInfo.GetSetMethod(Boolean).)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodGetValue(Object, Object())Gets the value of the indexed property by calling the property's getter method. (Overrides PropertyInfo.GetValue(Object, Object()).)
Public methodGetValue(Object, BindingFlags, Binder, Object(), CultureInfo)Gets the value of a property having the specified binding, index, and CultureInfo. (Overrides PropertyInfo.GetValue(Object, BindingFlags, Binder, Object(), CultureInfo).)
Public methodIsDefinedIndicates whether one or more instance of attributeType is defined on this property. (Overrides MemberInfo.IsDefined(Type, Boolean).)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodSetConstantSets the default value of this property.
Public methodSetCustomAttribute(CustomAttributeBuilder)Set a custom attribute using a custom attribute builder.
Public methodSetCustomAttribute(ConstructorInfo, Byte())Set a custom attribute using a specified custom attribute blob.
Public methodSetGetMethodSets the method that gets the property value.
Public methodSetSetMethodSets the method that sets the property value.
Public methodSetValue(Object, Object, Object())Sets the value of the property with optional index values for index properties. (Overrides PropertyInfo.SetValue(Object, Object, Object()).)
Public methodSetValue(Object, Object, BindingFlags, Binder, Object(), CultureInfo)Sets the property value for the given object to the given value. (Overrides PropertyInfo.SetValue(Object, Object, BindingFlags, Binder, Object(), CultureInfo).)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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  NameDescription
Explicit interface implemetationPrivate method_MemberInfo.GetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from MemberInfo.)
Explicit interface implemetationPrivate method_MemberInfo.GetTypeGets a Type object representing the MemberInfo class. (Inherited from MemberInfo.)
Explicit interface implemetationPrivate method_MemberInfo.GetTypeInfoRetrieves the type information for an object, which can then be used to get the type information for an interface. (Inherited from MemberInfo.)
Explicit interface implemetationPrivate method_MemberInfo.GetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from MemberInfo.)
Explicit interface implemetationPrivate method_MemberInfo.InvokeProvides access to properties and methods exposed by an object. (Inherited from MemberInfo.)
Explicit interface implemetationPrivate method_PropertyBuilder.GetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers.
Explicit interface implemetationPrivate method_PropertyBuilder.GetTypeInfoRetrieves the type information for an object, which can then be used to get the type information for an interface.
Explicit interface implemetationPrivate method_PropertyBuilder.GetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1).
Explicit interface implemetationPrivate method_PropertyBuilder.InvokeProvides access to properties and methods exposed by an object.
Explicit interface implemetationPrivate method_PropertyInfo.GetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from PropertyInfo.)
Explicit interface implemetationPrivate method_PropertyInfo.GetTypeGets a Type object representing the PropertyInfo type. (Inherited from PropertyInfo.)
Explicit interface implemetationPrivate method_PropertyInfo.GetTypeInfoRetrieves the type information for an object, which can then be used to get the type information for an interface. (Inherited from PropertyInfo.)
Explicit interface implemetationPrivate method_PropertyInfo.GetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from PropertyInfo.)
Explicit interface implemetationPrivate method_PropertyInfo.InvokeProvides access to properties and methods exposed by an object. (Inherited from PropertyInfo.)
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A PropertyBuilder is always associated with a TypeBuilder. The TypeBuilder. DefineProperty method will return a new PropertyBuilder to a client.

NoteNote

The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: MayLeakOnAbort. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

The following code sample demonstrates how to implement properties in a dynamic type using a PropertyBuilder obtained via TypeBuilder.DefineProperty to create the property framework and an associated MethodBuilder to implement the IL logic within the property.


Imports System
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit

Class PropertyBuilderDemo

   Public Shared Function BuildDynamicTypeWithProperties() As Type
      Dim myDomain As AppDomain = Thread.GetDomain()
      Dim myAsmName As New AssemblyName()
      myAsmName.Name = "MyDynamicAssembly"

      ' To generate a persistable assembly, specify AssemblyBuilderAccess.RunAndSave.
      Dim myAsmBuilder As AssemblyBuilder = myDomain.DefineDynamicAssembly(myAsmName, _
                                                        AssemblyBuilderAccess.RunAndSave)

      ' Generate a persistable, single-module assembly.
      Dim myModBuilder As ModuleBuilder = _
          myAsmBuilder.DefineDynamicModule(myAsmName.Name, myAsmName.Name & ".dll")

      Dim myTypeBuilder As TypeBuilder = myModBuilder.DefineType("CustomerData", TypeAttributes.Public)

      ' Define a private field to hold the property value.
      Dim customerNameBldr As FieldBuilder = myTypeBuilder.DefineField("customerName", _
                                             GetType(String), FieldAttributes.Private)

      ' The last argument of DefineProperty is Nothing, because the
      ' property has no parameters. (If you don't specify Nothing, you must
      ' specify an array of Type objects. For a parameterless property,
      ' use an array with no elements: New Type() {})
      Dim custNamePropBldr As PropertyBuilder = _
          myTypeBuilder.DefineProperty("CustomerName", _
                                       PropertyAttributes.HasDefault, _
                                       GetType(String), _
                                       Nothing)

      ' The property set and property get methods require a special
      ' set of attributes.
      Dim getSetAttr As MethodAttributes = _
          MethodAttributes.Public Or MethodAttributes.SpecialName _
              Or MethodAttributes.HideBySig

      ' Define the "get" accessor method for CustomerName.
      Dim custNameGetPropMthdBldr As MethodBuilder = _
          myTypeBuilder.DefineMethod("GetCustomerName", _
                                     getSetAttr, _
                                     GetType(String), _
                                     Type.EmptyTypes)

      Dim custNameGetIL As ILGenerator = custNameGetPropMthdBldr.GetILGenerator()

      custNameGetIL.Emit(OpCodes.Ldarg_0)
      custNameGetIL.Emit(OpCodes.Ldfld, customerNameBldr)
      custNameGetIL.Emit(OpCodes.Ret)

      ' Define the "set" accessor method for CustomerName.
      Dim custNameSetPropMthdBldr As MethodBuilder = _
          myTypeBuilder.DefineMethod("get_CustomerName", _
                                     getSetAttr, _
                                     Nothing, _
                                     New Type() {GetType(String)})

      Dim custNameSetIL As ILGenerator = custNameSetPropMthdBldr.GetILGenerator()

      custNameSetIL.Emit(OpCodes.Ldarg_0)
      custNameSetIL.Emit(OpCodes.Ldarg_1)
      custNameSetIL.Emit(OpCodes.Stfld, customerNameBldr)
      custNameSetIL.Emit(OpCodes.Ret)

      ' Last, we must map the two methods created above to our PropertyBuilder to 
      ' their corresponding behaviors, "get" and "set" respectively. 
      custNamePropBldr.SetGetMethod(custNameGetPropMthdBldr)
      custNamePropBldr.SetSetMethod(custNameSetPropMthdBldr)

      Dim retval As Type = myTypeBuilder.CreateType()

      ' Save the assembly so it can be examined with Ildasm.exe,
      ' or referenced by a test program.
      myAsmBuilder.Save(myAsmName.Name & ".dll")
      return retval
   End Function 'BuildDynamicTypeWithProperties


   Public Shared Sub Main()
      Dim custDataType As Type = BuildDynamicTypeWithProperties()

      Dim custDataPropInfo As PropertyInfo() = custDataType.GetProperties()
      Dim pInfo As PropertyInfo
      For Each pInfo In  custDataPropInfo
         Console.WriteLine("Property '{0}' created!", pInfo.ToString())
      Next pInfo

      Console.WriteLine("---")
      ' Note that when invoking a property, you need to use the proper BindingFlags -
      ' BindingFlags.SetProperty when you invoke the "set" behavior, and 
      ' BindingFlags.GetProperty when you invoke the "get" behavior. Also note that
      ' we invoke them based on the name we gave the property, as expected, and not
      ' the name of the methods we bound to the specific property behaviors.
      Dim custData As Object = Activator.CreateInstance(custDataType)
      custDataType.InvokeMember("CustomerName", BindingFlags.SetProperty, Nothing, _
                                custData, New Object() {"Joe User"})

      Console.WriteLine("The customerName field of instance custData has been set to '{0}'.", _
                        custDataType.InvokeMember("CustomerName", BindingFlags.GetProperty, _
                        Nothing, custData, New Object() {}))
   End Sub 'Main
End Class 'PropertyBuilderDemo


' --- O U T P U T ---
' The output should be as follows:
' -------------------
' Property 'System.String CustomerName [System.String]' created!
' ---
' The customerName field of instance custData has been set to 'Joe User'.
' -------------------


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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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