ConstructorBuilder.SetCustomAttribute Method    
Definition
Important
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Sets a custom attribute.
Overloads
| SetCustomAttribute(CustomAttributeBuilder) | Set a custom attribute using a custom attribute builder. | 
| SetCustomAttribute(ConstructorInfo, Byte[]) | Set a custom attribute using a specified custom attribute blob. | 
SetCustomAttribute(CustomAttributeBuilder)
- Source:
- ConstructorBuilder.cs
- Source:
- ConstructorBuilder.cs
- Source:
- ConstructorBuilder.cs
- Source:
- ConstructorBuilder.cs
Set a custom attribute using a custom attribute builder.
public:
 void SetCustomAttribute(System::Reflection::Emit::CustomAttributeBuilder ^ customBuilder);public void SetCustomAttribute(System.Reflection.Emit.CustomAttributeBuilder customBuilder);member this.SetCustomAttribute : System.Reflection.Emit.CustomAttributeBuilder -> unitPublic Sub SetCustomAttribute (customBuilder As CustomAttributeBuilder)Parameters
- customBuilder
- CustomAttributeBuilder
An instance of a helper class to define the custom attribute.
Exceptions
customBuilder is null.
Examples
The following code sample illustrates the use of SetCustomAttribute of the context of a ConstructorBuilder, passing a CustomAttributeBuilder.
using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
[AttributeUsage(AttributeTargets.All, AllowMultiple = false)]
public class MyAttribute : Attribute
{
   public String myString;
   public int myInteger;
   public MyAttribute(String myString, int myInteger)
   {
      this.myString = myString;
      this.myInteger = myInteger;
   }
}
public class MyConstructorBuilder
{
   public static void Main()
   {
      Type myHelloworld = MyCreateCallee(Thread.GetDomain());
      ConstructorInfo myConstructor = myHelloworld.GetConstructor(new Type[]{typeof(String)});
      object[] myAttributes1 = myConstructor.GetCustomAttributes(true);
      Console.WriteLine("MyAttribute custom attribute contains  ");
      for(int index=0; index < myAttributes1.Length; index++)
      {
         if(myAttributes1[index] is MyAttribute)
         {
            Console.WriteLine("The value of myString is : "
                                       + ((MyAttribute)myAttributes1[index]).myString);
            Console.WriteLine("The value of myInteger is : "
                                       + ((MyAttribute)myAttributes1[index]).myInteger);
         }
      }
   }
   private static Type MyCreateCallee(AppDomain domain)
   {
      AssemblyName myAssemblyName = new AssemblyName();
      myAssemblyName.Name = "EmittedAssembly";
      // Define a dynamic assembly in the current application domain.
      AssemblyBuilder myAssembly =
                  domain.DefineDynamicAssembly(myAssemblyName,AssemblyBuilderAccess.Run);
      // Define a dynamic module in this assembly.
      ModuleBuilder myModuleBuilder = myAssembly.DefineDynamicModule("EmittedModule");
       // Construct a 'TypeBuilder' given the name and attributes.
      TypeBuilder myTypeBuilder = myModuleBuilder.DefineType("HelloWorld",
         TypeAttributes.Public);
      // Define a constructor of the dynamic class.
      ConstructorBuilder myConstructor = myTypeBuilder.DefineConstructor(
               MethodAttributes.Public, CallingConventions.Standard, new Type[]{typeof(String)});
      ILGenerator myILGenerator = myConstructor.GetILGenerator();
      myILGenerator.Emit(OpCodes.Ldstr, "Constructor is invoked");
      myILGenerator.Emit(OpCodes.Ldarg_1);
      MethodInfo myMethodInfo =
                     typeof(Console).GetMethod("WriteLine",new Type[]{typeof(string)});
      myILGenerator.Emit(OpCodes.Call, myMethodInfo);
      myILGenerator.Emit(OpCodes.Ret);
      Type myType = typeof(MyAttribute);
      ConstructorInfo myConstructorInfo = myType.GetConstructor(new Type[2]{typeof(String), typeof(int)});
      CustomAttributeBuilder attributeBuilder =
         new CustomAttributeBuilder(myConstructorInfo, new object[2]{"Hello", 2});
      try
      {
         myConstructor.SetCustomAttribute(attributeBuilder);
      }
      catch(ArgumentNullException ex)
      {
         Console.WriteLine("The following exception has occurred : "+ex.Message);
      }
      catch(Exception ex)
      {
         Console.WriteLine("The following exception has occurred : "+ex.Message);
      }
      return myTypeBuilder.CreateType();
   }
}
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
<AttributeUsage(AttributeTargets.All, AllowMultiple := False)>  _
Public Class MyAttribute
   Inherits Attribute
   Public myString As String
   Public myInteger As Integer
   
   Public Sub New(myString As String, myInteger As Integer)
      Me.myString = myString
      Me.myInteger = myInteger
   End Sub
End Class
Public Class MyConstructorBuilder
   
   Public Shared Sub Main()
      Dim myHelloworld As Type = MyCreateCallee(Thread.GetDomain())
      Dim myConstructor As ConstructorInfo = myHelloworld.GetConstructor(New Type() _ 
                                                                       {GetType(String)})
      Dim myAttributes1 As Object() = myConstructor.GetCustomAttributes(True)
      Console.WriteLine("MyAttribute custom attribute contains  ")
      Dim index As Integer
      For index = 0 To myAttributes1.Length - 1
         If TypeOf myAttributes1(index) Is MyAttribute Then
            Console.WriteLine("The value of myString is : " + CType(myAttributes1(index), _ 
                                                                       MyAttribute).myString)
            Console.WriteLine("The value of myInteger is : " + CType(myAttributes1(index), _ 
                                                            MyAttribute).myInteger.ToString())
         End If
      Next index
   End Sub
   
   Private Shared Function MyCreateCallee(domain As AppDomain) As Type
      Dim myAssemblyName As New AssemblyName()
      myAssemblyName.Name = "EmittedAssembly"
      ' Define a dynamic assembly in the current application domain.
      Dim myAssembly As AssemblyBuilder = domain.DefineDynamicAssembly _ 
                                          (myAssemblyName, AssemblyBuilderAccess.Run)
      ' Define a dynamic module in this assembly.
      Dim myModuleBuilder As ModuleBuilder = myAssembly.DefineDynamicModule("EmittedModule")
      ' Construct a 'TypeBuilder' given the name and attributes.
      Dim myTypeBuilder As TypeBuilder = myModuleBuilder.DefineType _ 
                                                       ("HelloWorld", TypeAttributes.Public)
      ' Define a constructor of the dynamic class.
      Dim myConstructor As ConstructorBuilder = myTypeBuilder.DefineConstructor _ 
             (MethodAttributes.Public, CallingConventions.Standard, New Type() {GetType(String)})
      Dim myILGenerator As ILGenerator = myConstructor.GetILGenerator()
      myILGenerator.Emit(OpCodes.Ldstr, "Constructor is invoked")
      myILGenerator.Emit(OpCodes.Ldarg_1)
      Dim myMethodInfo As MethodInfo = GetType(Console).GetMethod("WriteLine", New Type() _ 
                                                                           {GetType(String)})
      myILGenerator.Emit(OpCodes.Call, myMethodInfo)
      myILGenerator.Emit(OpCodes.Ret)
      Dim myType As Type = GetType(MyAttribute)
      Dim myConstructorInfo As ConstructorInfo = myType.GetConstructor(New Type(1) _ 
                                                           {GetType(String), GetType(Integer)})
      Dim attributeBuilder As New CustomAttributeBuilder _ 
                                  (myConstructorInfo, New Object(1) {"Hello", 2})
      Try
         myConstructor.SetCustomAttribute(attributeBuilder)
      Catch ex As ArgumentNullException
         Console.WriteLine("The following exception has occurred : " + ex.Message)
      Catch ex As Exception
         Console.WriteLine("The following exception has occurred : " + ex.Message)
      End Try
      Return myTypeBuilder.CreateType()
   End Function 'MyCreateCallee
End Class
Applies to
SetCustomAttribute(ConstructorInfo, Byte[])
- Source:
- ConstructorBuilder.cs
- Source:
- ConstructorBuilder.cs
- Source:
- ConstructorBuilder.cs
- Source:
- ConstructorBuilder.cs
Set a custom attribute using a specified custom attribute blob.
public:
 void SetCustomAttribute(System::Reflection::ConstructorInfo ^ con, cli::array <System::Byte> ^ binaryAttribute);public void SetCustomAttribute(System.Reflection.ConstructorInfo con, byte[] binaryAttribute);[System.Runtime.InteropServices.ComVisible(true)]
public void SetCustomAttribute(System.Reflection.ConstructorInfo con, byte[] binaryAttribute);member this.SetCustomAttribute : System.Reflection.ConstructorInfo * byte[] -> unit[<System.Runtime.InteropServices.ComVisible(true)>]
member this.SetCustomAttribute : System.Reflection.ConstructorInfo * byte[] -> unitPublic Sub SetCustomAttribute (con As ConstructorInfo, binaryAttribute As Byte())Parameters
- con
- ConstructorInfo
The constructor for the custom attribute.
- binaryAttribute
- Byte[]
A byte blob representing the attributes.
- Attributes
Exceptions
con or binaryAttribute is null.
Examples
The following code sample illustrates the use of SetCustomAttribute of the context of a ConstructorBuilder, passing a byte blob.
using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
[AttributeUsage(AttributeTargets.All, AllowMultiple = false)]
public class MyAttribute : Attribute
{
   public bool myBoolean;
   public MyAttribute(bool myBoolean)
   {
      this.myBoolean = myBoolean;
   }
}
public class MyConstructorBuilder
{
   public static void Main()
   {
      Type myHelloworld = MyCreateCallee(Thread.GetDomain());
      ConstructorInfo myConstructor = myHelloworld.GetConstructor(new Type[]{typeof(String)});
      object[] myAttributes1 = myConstructor.GetCustomAttributes(true);
      Console.WriteLine("MyAttribute custom attribute contains  ");
      for(int index=0; index < myAttributes1.Length; index++)
      {
         if(myAttributes1[index] is MyAttribute)
         {
            Console.WriteLine("myBoolean : " + ((MyAttribute)myAttributes1[index]).myBoolean);
         }
      }
   }
   private static Type MyCreateCallee(AppDomain domain)
   {
      AssemblyName myAssemblyName = new AssemblyName();
      myAssemblyName.Name = "EmittedAssembly";
      // Define a dynamic assembly in the current application domain.
      AssemblyBuilder myAssembly =
                  domain.DefineDynamicAssembly(myAssemblyName,AssemblyBuilderAccess.Run);
      // Define a dynamic module in this assembly.
      ModuleBuilder myModuleBuilder = myAssembly.DefineDynamicModule("EmittedModule");
      // Construct a 'TypeBuilder' given the name and attributes.
      TypeBuilder myTypeBuilder = myModuleBuilder.DefineType("HelloWorld",
         TypeAttributes.Public);
      // Define a constructor of the dynamic class.
      ConstructorBuilder myConstructor = myTypeBuilder.DefineConstructor(
               MethodAttributes.Public, CallingConventions.Standard, new Type[]{typeof(String)});
      ILGenerator myILGenerator = myConstructor.GetILGenerator();
      myILGenerator.Emit(OpCodes.Ldstr, "Constructor is invoked");
      myILGenerator.Emit(OpCodes.Ldarg_1);
      MethodInfo myMethodInfo =
                     typeof(Console).GetMethod("WriteLine",new Type[]{typeof(string)});
      myILGenerator.Emit(OpCodes.Call, myMethodInfo);
      myILGenerator.Emit(OpCodes.Ret);
      Type myType = typeof(MyAttribute);
      ConstructorInfo myConstructorInfo = myType.GetConstructor(new Type[]{typeof(bool)});
      try
      {
         myConstructor.SetCustomAttribute(myConstructorInfo, new byte[]{01,00,01});
      }
      catch(ArgumentNullException ex)
      {
         Console.WriteLine("The following exception has occurred : "+ex.Message);
      }
      catch(Exception ex)
      {
         Console.WriteLine("The following exception has occurred : "+ex.Message);
      }
      return myTypeBuilder.CreateType();
   }
}
Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
<AttributeUsage(AttributeTargets.All, AllowMultiple := False)>  _
Public Class MyAttribute
   Inherits Attribute
   Public myBoolean As Boolean
   Public Sub New(myBoolean As Boolean)
      Me.myBoolean = myBoolean
   End Sub
End Class
Public Class MyConstructorBuilder
   Public Shared Sub Main()
      Dim myHelloworld As Type = MyCreateCallee(Thread.GetDomain())
      Dim myConstructor As ConstructorInfo = myHelloworld.GetConstructor(New Type() _
                                                                        {GetType(String)})
      Dim myAttributes1 As Object() = myConstructor.GetCustomAttributes(True)
      Console.WriteLine("MyAttribute custom attribute contains  ")
      Dim index As Integer
      For index = 0 To myAttributes1.Length - 1
         If TypeOf myAttributes1(index) Is MyAttribute Then
            Console.WriteLine("myBoolean : " + _
                               CType(myAttributes1(index), MyAttribute).myBoolean.ToString())
         End If
      Next index
   End Sub
   Private Shared Function MyCreateCallee(domain As AppDomain) As Type
      Dim myAssemblyName As New AssemblyName()
      myAssemblyName.Name = "EmittedAssembly"
      ' Define a dynamic assembly in the current application domain.
      Dim myAssembly As AssemblyBuilder = domain.DefineDynamicAssembly _
                                       (myAssemblyName, AssemblyBuilderAccess.Run)
      ' Define a dynamic module in this assembly.
      Dim myModuleBuilder As ModuleBuilder = myAssembly.DefineDynamicModule("EmittedModule")
      ' Construct a 'TypeBuilder' given the name and attributes.
      Dim myTypeBuilder As TypeBuilder = myModuleBuilder.DefineType _
                                                       ("HelloWorld", TypeAttributes.Public)
      ' Define a constructor of the dynamic class.
      Dim myConstructor As ConstructorBuilder = myTypeBuilder.DefineConstructor _
                (MethodAttributes.Public, CallingConventions.Standard, New Type() {GetType(String)})
      Dim myILGenerator As ILGenerator = myConstructor.GetILGenerator()
      myILGenerator.Emit(OpCodes.Ldstr, "Constructor is invoked")
      myILGenerator.Emit(OpCodes.Ldarg_1)
      Dim myMethodInfo As MethodInfo = GetType(Console).GetMethod("WriteLine", New Type() _
                                                                          {GetType(String)})
      myILGenerator.Emit(OpCodes.Call, myMethodInfo)
      myILGenerator.Emit(OpCodes.Ret)
      Dim myType As Type = GetType(MyAttribute)
      Dim myConstructorInfo As ConstructorInfo = myType.GetConstructor(New Type() {GetType(Boolean)})
      Try
         myConstructor.SetCustomAttribute(myConstructorInfo, New Byte() {1, 0, 1})
      Catch ex As ArgumentNullException
         Console.WriteLine("The following exception has occurred : " + ex.Message)
      Catch ex As Exception
         Console.WriteLine("The following exception has occurred : " + ex.Message)
      End Try
      Return myTypeBuilder.CreateType()
   End Function 'MyCreateCallee
End Class
Remarks
For information on how to format binaryAttribute, see the metadata specification in Partition II of the Common Language Infrastructure (CLI) specification.