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Sets a custom attribute.
SetCustomAttribute(CustomAttributeBuilder) |
Set a custom attribute using a custom attribute builder. |
SetCustomAttribute(ConstructorInfo, Byte[]) |
Set a custom attribute using a specified custom attribute blob. |
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 -> unit
Public Sub SetCustomAttribute (customBuilder As CustomAttributeBuilder)
An instance of a helper class to define the custom attribute.
customBuilder
is null
.
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
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0 (package-provided), 2.1 |
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[] -> unit
Public Sub SetCustomAttribute (con As ConstructorInfo, binaryAttribute As Byte())
The constructor for the custom attribute.
A byte blob representing the attributes.
con
or binaryAttribute
is null
.
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
For information on how to format binaryAttribute
, see the metadata specification in Partition II of the Common Language Infrastructure (CLI) specification.
Product | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0 (package-provided), 2.1 |
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