BindingFlags Enumeration
Specifies flags that control binding and the way in which the search for members and types is conducted by reflection.
This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.
[Visual Basic] <Flags> <Serializable> Public Enum BindingFlags [C#] [Flags] [Serializable] public enum BindingFlags [C++] [Flags] [Serializable] __value public enum BindingFlags [JScript] public Flags Serializable enum BindingFlags
Remarks
These BindingFlags control binding for a great many classes in the System, System.Reflection, and System.Runtime namespaces that invoke, create, get, set, and find members and types.
BindingFlags are used in the following Type methods and other places such as MethodBase.Invoke:
- MethodBase.Invoke
- GetMembers
- GetEvents
- InvokeMember
- Activator.CreateInstance
- GetConstructor
- GetConstructors
- GetMethod
- GetMethods
- GetField
- GetFields
- GetEvent
- GetProperty
- GetProperties
- GetMember
- FindMembers
InvokeMember and GetMethod are especially important.
The binding flags are categorized as follows.
| Binding Flag | Purpose |
|---|---|
| DeclaredOnly | Access Control |
| FlattenHierarchy | Access Control |
| IgnoreCase | Access Control |
| IgnoreReturn | Access Control |
| Instance | Access Control |
| NonPublic | Access Control |
| Public | Access Control |
| Static | Access Control |
| ExactBinding | Change Type |
| OptionalParamBinding | Change Type |
| CreateInstance | Operation Type |
| GetField | Operation Type |
| SetField | Operation Type |
| GetProperty | Operation Type |
| SetProperty | Operation Type |
| InvokeMethod | Operation Type |
| PutDispProperty | Operation Type |
| PutRefDispProperty | Operation Type |
Note You must specify Instance or Static along with Public or NonPublic or no members will be returned.
The following table lists the coercions performed by the default Binder.ChangeType. This table applies especially to the ExactBinding binding flag.
| Source Type | Target Type |
|---|---|
| Any type | Its base type. |
| Any type | The interface it implements. |
| Char | UInt16, UInt32, Int32, UInt64, Int64, Single, Double |
| Byte | Char, UInt16, Int16, UInt32, Int32, UInt64, Int64, Single, Double |
| SByte | Int16, Int32, Int64, Single, Double |
| UInt16 | UInt32, Int32, UInt64, Int64, Single, Double |
| Int16 | Int32, Int64, Single, Double |
| UInt32 | UInt64, Int64, Single, Double |
| Int32 | Int64, Single, Double |
| UInt64 | Single, Double |
| Int64 | Single, Double |
| Single | Double |
| Non-reference | By-reference. |
Members
| Member name | Description | Value |
|---|---|---|
| CreateInstance Supported by the .NET Compact Framework. | Specifies that Reflection should create an instance of the specified type. Calls the constructor that matches the given arguments. The supplied member name is ignored. If the type of lookup is not specified, (Instance | Public) will apply. It is not possible to call a type initializer. | 512 |
| DeclaredOnly Supported by the .NET Compact Framework. | Specifies that only members declared at the level of the supplied type's hierarchy should be considered. Inherited members are not considered. | 2 |
| Default Supported by the .NET Compact Framework. | Specifies no binding flag. | 0 |
| ExactBinding Supported by the .NET Compact Framework. | Specifies that types of the supplied arguments must exactly match the types of the corresponding formal parameters. Reflection throws an exception if the caller supplies a non-null Binder object, since that implies that the caller is supplying BindToXXX implementations that will pick the appropriate method.
Reflection models the accessibility rules of the common type system. For example, if the caller is in the same assembly, the caller does not need special permissions for internal members. Otherwise, the caller needs ReflectionPermission. This is consistent with lookup of members that are protected, private, and so on. The general principle is that ChangeType should perform only widening coercions, which never lose data. An example of a widening coercion is coercing a value that is a 32-bit signed integer to a value that is a 64-bit signed integer. This is distinguished from a narrowing coercion, which may lose data. An example of a narrowing coercion is coercing a 64-bit signed integer to a 32-bit signed integer. The default binder ignores this flag, while custom binders can implement the semantics of this flag. | 65536 |
| FlattenHierarchy Supported by the .NET Compact Framework. | Specifies that static members up the hierarchy should be returned. Static members include fields, methods, events, and properties. Nested types are not returned. | 64 |
| GetField Supported by the .NET Compact Framework. | Specifies that the value of the specified field should be returned. | 1024 |
| GetProperty Supported by the .NET Compact Framework. | Specifies that the value of the specified property should be returned. | 4096 |
| IgnoreCase Supported by the .NET Compact Framework. | Specifies that the case of the member name should not be considered when binding. | 1 |
| IgnoreReturn Supported by the .NET Compact Framework. | Used in COM interop to specify that the return value of the member can be ignored. | 16777216 |
| Instance Supported by the .NET Compact Framework. | Specifies that instance members are to be included in the search. | 4 |
| InvokeMethod Supported by the .NET Compact Framework. | Specifies that a method is to be invoked. This may not be a constructor or a type initializer. | 256 |
| NonPublic Supported by the .NET Compact Framework. | Specifies that non-public members are to be included in the search. | 32 |
| OptionalParamBinding Supported by the .NET Compact Framework. | Returns the set of members whose parameter count matches the number of supplied arguments. This binding flag is used for methods with parameters that have default values and methods with variable arguments (varargs). This flag should only be used with Type.InvokeMember.
Parameters with default values are used only in calls where trailing arguments are omitted. They must be the last arguments. | 262144 |
| Public Supported by the .NET Compact Framework. | Specifies that public members are to be included in the search. | 16 |
| PutDispProperty Supported by the .NET Compact Framework. | Specifies that the PROPPUT member on a COM object should be invoked. PROPPUT specifies a property-setting function that uses a value. Use PutDispProperty if a property has both PROPPUT and PROPPUTREF and you need to distinguish which one is called. | 16384 |
| PutRefDispProperty Supported by the .NET Compact Framework. | Specifies that the PROPPUTREF member on a COM object should be invoked. PROPPUTREF specifies a property-setting function that uses a reference instead of a value. Use PutRefDispProperty if a property has both PROPPUT and PROPPUTREF and you need to distinguish which one is called. | 32768 |
| SetField Supported by the .NET Compact Framework. | Specifies that the value of the specified field should be set. | 2048 |
| SetProperty Supported by the .NET Compact Framework. | Specifies that the value of the specified property should be set. For COM properties, specifying this binding flag is equivalent to specifying PutDispProperty and PutRefDispProperty. | 8192 |
| Static Supported by the .NET Compact Framework. | Specifies that static members are to be included in the search. | 8 |
| SuppressChangeType Supported by the .NET Compact Framework. | Not implemented. | 131072 |
Example
[Visual Basic, C#, C++] The following example demonstrates each binding flag.
[Visual Basic] Imports System Imports System.Reflection Imports System.IO Class EntryPoint Overloads Shared Sub Main(ByVal args() As String) Invoke.Go() End Sub 'Main End Class 'EntryPoint Class Invoke Public Shared Sub Go() ' BindingFlags.InvokeMethod ' Call a static method. Dim t As Type = GetType(TestClass) Console.WriteLine() Console.WriteLine("Invoking a static method.") Console.WriteLine("-------------------------") t.InvokeMember("SayHello", BindingFlags.InvokeMethod, Nothing, Nothing, New Object() {}) ' BindingFlags.InvokeMethod ' Call an instance method. Dim c As New TestClass() Console.WriteLine() Console.WriteLine("Invoking an instance method.") Console.WriteLine("----------------------------") c.GetType().InvokeMember("AddUp", BindingFlags.InvokeMethod, Nothing, c, New Object() {}) c.GetType().InvokeMember("AddUp", BindingFlags.InvokeMethod, Nothing, c, New Object() {}) ' BindingFlags.InvokeMethod ' Call a method with parameters. Dim args() As Object = {100.09, 184.45} Dim result As Object Console.WriteLine() Console.WriteLine("Invoking a method with parameters.") Console.WriteLine("---------------------------------") result = t.InvokeMember("ComputeSum", BindingFlags.InvokeMethod, Nothing, Nothing, args) Console.WriteLine("{0} + {1} = {2}", args(0), args(1), result) ' BindingFlags.GetField, SetField Console.WriteLine() Console.WriteLine("Invoking a field (getting and setting.)") Console.WriteLine("--------------------------------------") ' Get a field value. result = t.InvokeMember("Name", BindingFlags.GetField, Nothing, c, New Object() {}) Console.WriteLine("Name == {0}", result) ' Set a field. t.InvokeMember("Name", BindingFlags.SetField, Nothing, c, New Object() {"NewName"}) result = t.InvokeMember("Name", BindingFlags.GetField, Nothing, c, New Object() {}) Console.WriteLine("Name == {0}", result) Console.WriteLine() Console.WriteLine("Invoking an indexed property (getting and setting.)") Console.WriteLine("--------------------------------------------------") ' BindingFlags.GetProperty ' Get an indexed property value. Dim index As Integer = 3 result = t.InvokeMember("Item", BindingFlags.GetProperty, Nothing, c, New Object() {index}) Console.WriteLine("Item[{0}] == {1}", index, result) ' BindingFlags.SetProperty ' Set an indexed property value. index = 3 t.InvokeMember("Item", BindingFlags.SetProperty, Nothing, c, New Object() {index, "NewValue"}) result = t.InvokeMember("Item", BindingFlags.GetProperty, Nothing, c, New Object() {index}) Console.WriteLine("Item[{0}] == {1}", index, result) Console.WriteLine() Console.WriteLine("Getting a field or property.") Console.WriteLine("----------------------------") ' BindingFlags.GetField ' Get a field or property. result = t.InvokeMember("Name", BindingFlags.GetField Or BindingFlags.GetProperty, Nothing, c, New Object() {}) Console.WriteLine("Name == {0}", result) ' BindingFlags.GetProperty result = t.InvokeMember("Value", BindingFlags.GetField Or BindingFlags.GetProperty, Nothing, c, New Object() {}) Console.WriteLine("Value == {0}", result) Console.WriteLine() Console.WriteLine("Invoking a method with named parameters.") Console.WriteLine("---------------------------------------") ' BindingFlags.InvokeMethod ' Call a method using named parameters. Dim argValues() As Object = {"Mouse", "Micky"} Dim argNames() As [String] = {"lastName", "firstName"} t.InvokeMember("PrintName", BindingFlags.InvokeMethod, Nothing, Nothing, argValues, Nothing, Nothing, argNames) Console.WriteLine() Console.WriteLine("Invoking a default member of a type.") Console.WriteLine("------------------------------------") ' BindingFlags.Default ' Call the default member of a type. Dim t3 As Type = GetType(TestClass2) t3.InvokeMember("", BindingFlags.InvokeMethod Or BindingFlags.Default, Nothing, New TestClass2(), New Object() {}) Console.WriteLine() Console.WriteLine("Invoking a method by reference.") Console.WriteLine("-------------------------------") ' BindingFlags.Static, NonPublic, and Public ' Invoking a member by reference. Dim m As MethodInfo = t.GetMethod("Swap") args = New Object(1) {} args(0) = 1 args(1) = 2 m.Invoke(New TestClass(), args) Console.WriteLine("{0}, {1}", args(0), args(1)) ' The string is case-sensitive. Dim type As Type = type.GetType("System.String") ' Check to see if the value is valid. If the object is null, the type does not exist. If type Is Nothing Then Console.WriteLine("Please ensure that you specify only valid types in the type field.") Console.WriteLine("The type name is case-sensitive.") Return End If ' Declare and populate the arrays to hold the information. ' You must declare either NonPublic or Public with Static or the search will not work. Dim fi As FieldInfo() = type.GetFields((BindingFlags.Static Or BindingFlags.NonPublic Or BindingFlags.Public)) ' BindingFlags.NonPublic Dim miNonPublic As MethodInfo() = type.GetMethods((BindingFlags.Static Or BindingFlags.NonPublic)) ' BindingFlags.Public Dim miPublic As MethodInfo() = type.GetMethods((BindingFlags.Static Or BindingFlags.Public)) ' Iterate through all the nonpublic methods. Dim method As MethodInfo For Each method In miNonPublic Console.WriteLine(method) Next method ' Iterate through all the public methods. For Each method In miPublic Console.WriteLine(method) Next method ' Iterate through all the fields. Dim f As FieldInfo For Each f In fi Console.WriteLine(f) Next f ' Call an instance method. Dim tc As New TestClass() Console.WriteLine() Console.WriteLine("Invoking an Instance method.") Console.WriteLine("----------------------------") tc.GetType().InvokeMember("AddUp", BindingFlags.Public Or BindingFlags.Instance Or BindingFlags.CreateInstance, Nothing, tc, New Object() {}) ' BindingFlags.CreateInstance ' Calling and creating an instance method. Console.WriteLine() Console.WriteLine("Invoking and creating an instance method.") Console.WriteLine("-----------------------------------------") tc.GetType().InvokeMember("AddUp", BindingFlags.Public Or BindingFlags.Instance Or BindingFlags.CreateInstance, Nothing, tc, New Object() {}) ' BindingFlags.DeclaredOnly Dim tc2 As New TestClass() Console.WriteLine() Console.WriteLine("DeclaredOnly members") Console.WriteLine("---------------------------------") Dim memInfo As System.Reflection.MemberInfo() = tc2.GetType().GetMembers(BindingFlags.DeclaredOnly) Dim i As Integer For i = 0 To memInfo.Length - 1 Console.WriteLine(memInfo(i).Name) Next i ' BindingFlags.SuppressChangeType Dim obj As New TestClass() Console.WriteLine() Console.WriteLine("Invoking static method - PrintName") Console.WriteLine("---------------------------------") Dim methInfo As System.Reflection.MethodInfo = obj.GetType().GetMethod("PrintName") methInfo.Invoke(obj, BindingFlags.SuppressChangeType Or BindingFlags.InvokeMethod, Nothing, New Object() {"Brad", "Smith"}, Nothing) ' BindingFlags.IgnoreCase Console.WriteLine() Console.WriteLine("Using IgnoreCase and invoking the PrintName method.") Console.WriteLine("---------------------------------------------------") methInfo = obj.GetType().GetMethod("PrintName") methInfo.Invoke(obj, BindingFlags.IgnoreCase Or BindingFlags.InvokeMethod, Nothing, New Object() {"brad", "smith"}, Nothing) ' BindingFlags.IgnoreReturn Console.WriteLine() Console.WriteLine("Using IgnoreReturn and invoking the PrintName method.") Console.WriteLine("-----------------------------------------------------") methInfo = obj.GetType().GetMethod("PrintName") methInfo.Invoke(obj, BindingFlags.IgnoreReturn Or BindingFlags.InvokeMethod, Nothing, New Object() {"Brad", "Smith"}, Nothing) ' BindingFlags.OptionalParamBinding Console.WriteLine() Console.WriteLine("Using OptionalParamBinding and invoking the PrintName method.") Console.WriteLine("-------------------------------------------------------------") methInfo = obj.GetType().GetMethod("PrintName") methInfo.Invoke(obj, BindingFlags.OptionalParamBinding Or BindingFlags.InvokeMethod, Nothing, New Object() {"Brad", "Smith"}, Nothing) ' BindingFlags.ExactBinding Console.WriteLine() Console.WriteLine("Using ExactBinding and invoking the PrintName method.") Console.WriteLine("-----------------------------------------------------") methInfo = obj.GetType().GetMethod("PrintName") methInfo.Invoke(obj, BindingFlags.ExactBinding Or BindingFlags.InvokeMethod, Nothing, New Object() {"Brad", "Smith"}, Nothing) ' BindingFlags.FlattenHierarchy Console.WriteLine() Console.WriteLine("Using FlattenHierarchy and invoking the PrintName method.") Console.WriteLine("---------------------------------------------------------") methInfo = obj.GetType().GetMethod("PrintName") methInfo.Invoke(obj, BindingFlags.FlattenHierarchy Or BindingFlags.InvokeMethod, Nothing, New Object() {"Brad", "Smith"}, Nothing) End Sub 'Go End Class 'Invoke Public Class TestClass Public Name As [String] Private values() As [Object] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} Default Public Property Item(ByVal index As Integer) As [Object] Get Return values(index) End Get Set(ByVal Value As [Object]) values(index) = Value End Set End Property Public ReadOnly Property Value() As [Object] Get Return "the value" End Get End Property Public Sub New() Name = "initialName" End Sub 'New Private methodCalled As Integer = 0 Public Shared Sub SayHello() Console.WriteLine("Hello") End Sub 'SayHello Public Sub AddUp() methodCalled += 1 Console.WriteLine("AddUp Called {0} times", methodCalled) End Sub 'AddUp Public Shared Function ComputeSum(ByVal d1 As Double, ByVal d2 As Double) As Double Return d1 + d2 End Function 'ComputeSum Public Shared Sub PrintName(ByVal firstName As [String], ByVal lastName As [String]) Console.WriteLine("{0},{1}", lastName, firstName) End Sub 'PrintName Public Sub PrintTime() Console.WriteLine(DateTime.Now) End Sub 'PrintTime Public Sub Swap(ByRef a As Integer, ByRef b As Integer) Dim x As Integer = a a = b b = x End Sub 'Swap End Class 'TestClass <DefaultMemberAttribute("PrintTime")> _ Public Class TestClass2 Public Sub PrintTime() Console.WriteLine(DateTime.Now) End Sub 'PrintTime End Class 'TestClass2 [C#] using System; using System.Reflection; using System.IO; namespace BindingFlagsSnippet { class EntryPoint { static void Main(string[] args) { Invoke.Go(); } } class Invoke { public static void Go() { // BindingFlags.InvokeMethod // Call a static method. Type t = typeof (TestClass); Console.WriteLine(); Console.WriteLine("Invoking a static method."); Console.WriteLine("-------------------------"); t.InvokeMember ("SayHello", BindingFlags.InvokeMethod, null, null, new object [] {}); // BindingFlags.InvokeMethod // Call an instance method. TestClass c = new TestClass (); Console.WriteLine(); Console.WriteLine("Invoking an instance method."); Console.WriteLine("----------------------------"); c.GetType().InvokeMember ("AddUp", BindingFlags.InvokeMethod, null, c, new object [] {}); c.GetType().InvokeMember ("AddUp", BindingFlags.InvokeMethod, null, c, new object [] {}); // BindingFlags.InvokeMethod // Call a method with parameters. object [] args = new object [] {100.09, 184.45}; object result; Console.WriteLine(); Console.WriteLine("Invoking a method with parameters."); Console.WriteLine("---------------------------------"); result = t.InvokeMember ("ComputeSum", BindingFlags.InvokeMethod, null, null, args); Console.WriteLine ("{0} + {1} = {2}", args[0], args[1], result); // BindingFlags.GetField, SetField Console.WriteLine(); Console.WriteLine("Invoking a field (getting and setting.)"); Console.WriteLine("--------------------------------------"); // Get a field value. result = t.InvokeMember ("Name", BindingFlags.GetField, null, c, new object [] {}); Console.WriteLine ("Name == {0}", result); // Set a field. t.InvokeMember ("Name", BindingFlags.SetField, null, c, new object [] {"NewName"}); result = t.InvokeMember ("Name", BindingFlags.GetField, null, c, new object [] {}); Console.WriteLine ("Name == {0}", result); Console.WriteLine(); Console.WriteLine("Invoking an indexed property (getting and setting.)"); Console.WriteLine("--------------------------------------------------"); // BindingFlags.GetProperty // Get an indexed property value. int index = 3; result = t.InvokeMember ("Item", BindingFlags.GetProperty, null, c, new object [] {index}); Console.WriteLine ("Item[{0}] == {1}", index, result); // BindingFlags.SetProperty // Set an indexed property value. index = 3; t.InvokeMember ("Item", BindingFlags.SetProperty, null, c, new object [] {index, "NewValue"}); result = t.InvokeMember ("Item", BindingFlags.GetProperty , null, c, new object [] {index}); Console.WriteLine ("Item[{0}] == {1}", index, result); Console.WriteLine(); Console.WriteLine("Getting a field or property."); Console.WriteLine("----------------------------"); // BindingFlags.GetField // Get a field or property. result = t.InvokeMember ("Name", BindingFlags.GetField | BindingFlags.GetProperty, null, c, new object [] {}); Console.WriteLine ("Name == {0}", result); // BindingFlags.GetProperty result = t.InvokeMember ("Value", BindingFlags.GetField | BindingFlags.GetProperty, null, c, new object [] {}); Console.WriteLine ("Value == {0}", result); Console.WriteLine(); Console.WriteLine("Invoking a method with named parameters."); Console.WriteLine("---------------------------------------"); // BindingFlags.InvokeMethod // Call a method using named parameters. object[] argValues = new object [] {"Mouse", "Micky"}; String [] argNames = new String [] {"lastName", "firstName"}; t.InvokeMember ("PrintName", BindingFlags.InvokeMethod, null, null, argValues, null, null, argNames); Console.WriteLine(); Console.WriteLine("Invoking a default member of a type."); Console.WriteLine("------------------------------------"); // BindingFlags.Default // Call the default member of a type. Type t3 = typeof (TestClass2); t3.InvokeMember ("", BindingFlags.InvokeMethod | BindingFlags.Default, null, new TestClass2(), new object [] {}); // BindingFlags.Static, NonPublic, and Public // Invoking a member by reference. Console.WriteLine(); Console.WriteLine("Invoking a method by reference."); Console.WriteLine("-------------------------------"); MethodInfo m = t.GetMethod("Swap"); args = new object[2]; args[0] = 1; args[1] = 2; m.Invoke(new TestClass(),args); Console.WriteLine ("{0}, {1}", args[0], args[1]); // The string is case-sensitive. Type type = Type.GetType("System.String"); // Check to see if the value is valid. If the object is null, the type does not exist. if (type == null) { Console.WriteLine("Please ensure that you specify only valid types in the type field."); Console.WriteLine("The type name is case-sensitive."); return; } // Declare and populate the arrays to hold the information. // You must declare either NonPublic or Public with Static or the search will not work. FieldInfo [] fi = type.GetFields (BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public); // BindingFlags.NonPublic MethodInfo [] miNonPublic = type.GetMethods (BindingFlags.Static | BindingFlags.NonPublic); // BindingFlags.Public MethodInfo [] miPublic = type.GetMethods (BindingFlags.Static | BindingFlags.Public); // Iterate through all the nonpublic methods. foreach (MethodInfo method in miNonPublic) { Console.WriteLine(method); } // Iterate through all the public methods. foreach (MethodInfo method in miPublic) { Console.WriteLine(method); } // Iterate through all the fields. foreach (FieldInfo f in fi) { Console.WriteLine(f); } // BindingFlags.Instance // Call an instance method. TestClass tc = new TestClass (); Console.WriteLine(); Console.WriteLine("Invoking an Instance method."); Console.WriteLine("----------------------------"); tc.GetType().InvokeMember ("AddUp", BindingFlags.Public | BindingFlags.Instance | BindingFlags.CreateInstance, null, tc, new object [] {}); // BindingFlags.CreateInstance // Calling and creating an instance method. Console.WriteLine(); Console.WriteLine("Invoking and creating an instance method."); Console.WriteLine("-----------------------------------------"); tc.GetType().InvokeMember ("AddUp", BindingFlags.Public | BindingFlags.Instance | BindingFlags.CreateInstance, null, tc, new object [] {}); // BindingFlags.DeclaredOnly TestClass tc2 = new TestClass(); Console.WriteLine(); Console.WriteLine("DeclaredOnly members"); Console.WriteLine("---------------------------------"); System.Reflection.MemberInfo[] memInfo = tc2.GetType().GetMembers(BindingFlags.DeclaredOnly); for(int i=0;i<memInfo.Length;i++) { Console.WriteLine(memInfo[i].Name); } // BindingFlags.SuppressChangeType TestClass obj = new TestClass(); Console.WriteLine(); Console.WriteLine("Invoking static method - PrintName"); Console.WriteLine("---------------------------------"); System.Reflection.MethodInfo methInfo = obj.GetType().GetMethod("PrintName"); methInfo.Invoke(obj,BindingFlags.SuppressChangeType | BindingFlags.InvokeMethod, null,new object[] {"Brad","Smith"},null); // BindingFlags.IgnoreCase Console.WriteLine(); Console.WriteLine("Using IgnoreCase and invoking the PrintName method."); Console.WriteLine("---------------------------------------------------"); methInfo = obj.GetType().GetMethod("PrintName"); methInfo.Invoke(obj,BindingFlags.IgnoreCase | BindingFlags.InvokeMethod, null,new object[] {"brad","smith"},null); // BindingFlags.IgnoreReturn Console.WriteLine(); Console.WriteLine("Using IgnoreReturn and invoking the PrintName method."); Console.WriteLine("-----------------------------------------------------"); methInfo = obj.GetType().GetMethod("PrintName"); methInfo.Invoke(obj,BindingFlags.IgnoreReturn | BindingFlags.InvokeMethod, null,new object[] {"Brad","Smith"},null); // BindingFlags.OptionalParamBinding Console.WriteLine(); Console.WriteLine("Using OptionalParamBinding and invoking the PrintName method."); Console.WriteLine("-------------------------------------------------------------"); methInfo = obj.GetType().GetMethod("PrintName"); methInfo.Invoke(obj,BindingFlags.OptionalParamBinding | BindingFlags.InvokeMethod, null,new object[] {"Brad","Smith"},null); // BindingFlags.ExactBinding Console.WriteLine(); Console.WriteLine("Using ExactBinding and invoking the PrintName method."); Console.WriteLine("-----------------------------------------------------"); methInfo = obj.GetType().GetMethod("PrintName"); methInfo.Invoke(obj,BindingFlags.ExactBinding | BindingFlags.InvokeMethod, null,new object[] {"Brad","Smith"},null); // BindingFlags.FlattenHierarchy Console.WriteLine(); Console.WriteLine("Using FlattenHierarchy and invoking the PrintName method."); Console.WriteLine("---------------------------------------------------------"); methInfo = obj.GetType().GetMethod("PrintName"); methInfo.Invoke(obj,BindingFlags.FlattenHierarchy | BindingFlags.InvokeMethod, null,new object[] {"Brad","Smith"},null); } } public class TestClass { public String Name; private Object [] values = new Object [] {0, 1,2,3,4,5,6,7,8,9}; public Object this [int index] { get { return values[index]; } set { values[index] = value; } } public Object Value { get { return "the value"; } } public TestClass () { Name = "initialName"; } int methodCalled = 0; public static void SayHello () { Console.WriteLine ("Hello"); } public void AddUp () { methodCalled++; Console.WriteLine ("AddUp Called {0} times", methodCalled); } public static double ComputeSum (double d1, double d2) { return d1 + d2; } public static void PrintName (String firstName, String lastName) { Console.WriteLine ("{0},{1}", lastName,firstName); } public void PrintTime () { Console.WriteLine (DateTime.Now); } public void Swap(ref int a, ref int b) { int x = a; a = b; b = x; } } [DefaultMemberAttribute ("PrintTime")] public class TestClass2 { public void PrintTime () { Console.WriteLine (DateTime.Now); } } } [C++] #using <mscorlib.dll> using namespace System; using namespace System::Collections; using namespace System::Reflection; using namespace System::IO; //namespace BindingFlagsSnippet { public __gc class TestClass { public: String* Name; private: Object* values[]; public: __property Object* get_Item(int index) { return values->Item[index]; } __property void set_Item(int index, Object* value) { values->Item[index] = value; } __property Object* get_Value() { return S"the value"; } int methodCalled; TestClass () { Name = S"initialName"; Object* o[] = {__box(0), __box(1), __box(2), __box(3), __box(4), __box(5), __box(6), __box(7), __box(8), __box(9)}; values = o; methodCalled = 0; } static void SayHello () { Console::WriteLine (S"Hello"); } void AddUp () { methodCalled++; Console::WriteLine (S"AddUp Called {0} times", __box(methodCalled)); } static double ComputeSum (double d1, double d2) { return d1 + d2; } static void PrintName (String* firstName, String* lastName) { Console::WriteLine (S"{0},{1}", lastName, firstName); } void PrintTime () { Console::WriteLine (__box(DateTime::Now)); } void Swap(int __gc* a, int __gc* b) { int x = *a; *a = *b; *b = x; } }; [DefaultMemberAttribute (S"PrintTime")] public __gc class TestClass2 { public: void PrintTime () { Console::WriteLine (__box(DateTime::Now)); } }; class Invoke { public: static void Go() { // BindingFlags::InvokeMethod // Call a static method. Type* t = __typeof (TestClass); Console::WriteLine(); Console::WriteLine(S"Invoking a static method."); Console::WriteLine(S"-------------------------"); Object* obj1[]; t->InvokeMember (S"SayHello", BindingFlags::InvokeMethod, 0, 0, obj1); // BindingFlags::InvokeMethod // Call an instance method. TestClass* c = new TestClass (); Console::WriteLine(); Console::WriteLine(S"Invoking an instance method."); Console::WriteLine(S"----------------------------"); c->GetType()->InvokeMember (S"AddUp", BindingFlags::InvokeMethod, 0, c, obj1); c->GetType()->InvokeMember (S"AddUp", BindingFlags::InvokeMethod, 0, c, obj1); // BindingFlags::InvokeMethod // Call a method with parameters. Object* args[] = {__box(100.09), __box(184.45)}; Object* result; Console::WriteLine(); Console::WriteLine(S"Invoking a method with parameters."); Console::WriteLine(S"---------------------------------"); result = t->InvokeMember (S"ComputeSum", BindingFlags::InvokeMethod, 0, 0, args); Console::WriteLine (S" {0} + {1} = {2}", args->Item[0], args->Item[1], result); // BindingFlags::GetField, SetField Console::WriteLine(); Console::WriteLine(S"Invoking a field (getting and setting.)"); Console::WriteLine(S"--------------------------------------"); // Get a field value. result = t->InvokeMember (S"Name", BindingFlags::GetField, 0, c, obj1); Console::WriteLine (S"Name == {0}", result); // Set a field. Object* obj2[] = {S"NewName"}; t->InvokeMember (S"Name", BindingFlags::SetField, 0, c, obj2); result = t->InvokeMember (S"Name", BindingFlags::GetField, 0, c, obj1); Console::WriteLine (S"Name == {0}", result); Console::WriteLine(); Console::WriteLine(S"Invoking an indexed property (getting and setting.)"); Console::WriteLine(S"--------------------------------------------------"); // BindingFlags::GetProperty // Get an indexed property value. int index = 3; Object* obj3[] = {__box(index)}; result = t->InvokeMember (S"Item", BindingFlags::GetProperty, 0, c, obj3); Console::WriteLine (S"Item->Item[ {0}] == {1}", __box(index), result); // BindingFlags::SetProperty // Set an indexed property value. index = 3; Object* obj4[] = {__box(index), S"NewValue"}; t->InvokeMember (S"Item", BindingFlags::SetProperty, 0, c, obj4); result = t->InvokeMember (S"Item", BindingFlags::GetProperty , 0, c, obj3); Console::WriteLine (S"Item->Item[ {0}] == {1}", __box(index), result); Console::WriteLine(); Console::WriteLine(S"Getting a field or property."); Console::WriteLine(S"----------------------------"); // BindingFlags::GetField // Get a field or property. result = t->InvokeMember (S"Name", static_cast<BindingFlags>(BindingFlags::GetField | BindingFlags::GetProperty), 0, c, obj1); Console::WriteLine (S"Name == {0}", result); // BindingFlags::GetProperty result = t->InvokeMember (S"Value", static_cast<BindingFlags>(BindingFlags::GetField | BindingFlags::GetProperty), 0, c, obj1); Console::WriteLine (S"Value == {0}", result); Console::WriteLine(); Console::WriteLine(S"Invoking a method with named parameters."); Console::WriteLine(S"---------------------------------------"); // BindingFlags::InvokeMethod // Call a method using named parameters. Object* argValues[] = {S"Mouse", S"Micky"}; String* argNames[] = {S"lastName", S"firstName"}; t->InvokeMember (S"PrintName", BindingFlags::InvokeMethod, 0, 0, argValues, 0, 0, argNames); Console::WriteLine(); Console::WriteLine(S"Invoking a default member of a type."); Console::WriteLine(S"------------------------------------"); // BindingFlags::Default // Call the default member of a type. Type* t3 = __typeof (TestClass2); t3->InvokeMember (S"", static_cast<BindingFlags>(BindingFlags::InvokeMethod | BindingFlags::Default), 0, new TestClass2(), obj1); // BindingFlags::Static, NonPublic, and Public // Invoking a member by reference. Console::WriteLine(); Console::WriteLine(S"Invoking a method by reference."); Console::WriteLine(S"-------------------------------"); MethodInfo* m = t->GetMethod(S"Swap"); args = new Object*[2]; args[0] = __box(1); args[1] = __box(2); m->Invoke(new TestClass(), args); Console::WriteLine (S"{0}, {1}", args->Item[0], args->Item[1]); // The String* is case-sensitive. Type* type = Type::GetType(S"System.String"); // Check to see if the value is valid. If the Object* is 0, the type does not exist. if (type == 0) { Console::WriteLine(S"Please ensure that you specify only valid types in the type field."); Console::WriteLine(S"The type name is case-sensitive."); return; } // Declare and populate the arrays to hold the information. // You must declare either NonPublic or Public with Static or the search will not work. FieldInfo* fi[] = type->GetFields (static_cast<BindingFlags>(BindingFlags::Static | BindingFlags::NonPublic | BindingFlags::Public)); // BindingFlags::NonPublic MethodInfo* miNonPublic[] = type->GetMethods (static_cast<BindingFlags>(BindingFlags::Static | BindingFlags::NonPublic)); // BindingFlags::Public MethodInfo* miPublic[] = type->GetMethods (static_cast<BindingFlags>(BindingFlags::Static | BindingFlags::Public)); // Iterate through all the nonpublic methods. IEnumerator* myEnum1 = miNonPublic->GetEnumerator(); while (myEnum1->MoveNext()) { MethodInfo* method = __try_cast<MethodInfo*>(myEnum1->Current); Console::WriteLine(method); } // Iterate through all the public methods. IEnumerator* myEnum2 = miPublic->GetEnumerator(); while (myEnum2->MoveNext()) { MethodInfo* method = __try_cast<MethodInfo*>(myEnum2->Current); Console::WriteLine(method); } // Iterate through all the fields. IEnumerator* myEnum3 = fi->GetEnumerator(); while (myEnum3->MoveNext()) { FieldInfo* f = __try_cast<FieldInfo*>(myEnum3->Current); Console::WriteLine(f); } // BindingFlags::Instance // Call an instance method. TestClass* tc = new TestClass (); Console::WriteLine(); Console::WriteLine(S"Invoking an Instance method."); Console::WriteLine(S"----------------------------"); tc->GetType()->InvokeMember (S"AddUp", static_cast<BindingFlags>(BindingFlags::Public | BindingFlags::Instance | BindingFlags::CreateInstance), 0, tc, obj1); // BindingFlags::CreateInstance // Calling and creating an instance method. Console::WriteLine(); Console::WriteLine(S"Invoking and creating an instance method."); Console::WriteLine(S"-----------------------------------------"); tc->GetType()->InvokeMember (S"AddUp", static_cast<BindingFlags>(BindingFlags::Public | BindingFlags::Instance | BindingFlags::CreateInstance), 0, tc, obj1); // BindingFlags::DeclaredOnly TestClass* tc2 = new TestClass(); Console::WriteLine(); Console::WriteLine(S"DeclaredOnly members"); Console::WriteLine(S"---------------------------------"); System::Reflection::MemberInfo* memInfo[] = tc2->GetType()->GetMembers(BindingFlags::DeclaredOnly); for (int i=0;i<memInfo->Length;i++) { Console::WriteLine(memInfo[i]->Name); } // BindingFlags::SuppressChangeType TestClass* obj = new TestClass(); Console::WriteLine(); Console::WriteLine(S"Invoking static method - PrintName"); Console::WriteLine(S"---------------------------------"); System::Reflection::MethodInfo* methInfo = obj->GetType()->GetMethod(S"PrintName"); Object* args1[] = {S"Brad", S"Smith"}; methInfo->Invoke(obj, static_cast<BindingFlags>(BindingFlags::SuppressChangeType | BindingFlags::InvokeMethod), 0, args1, 0); // BindingFlags::IgnoreCase Console::WriteLine(); Console::WriteLine(S"Using IgnoreCase and invoking the PrintName method."); Console::WriteLine(S"---------------------------------------------------"); methInfo = obj->GetType()->GetMethod(S"PrintName"); Object* args2[] = {S"brad", S"smith"}; methInfo->Invoke(obj, static_cast<BindingFlags>(BindingFlags::IgnoreCase | BindingFlags::InvokeMethod), 0, args2, 0); // BindingFlags::IgnoreReturn Console::WriteLine(); Console::WriteLine(S"Using IgnoreReturn and invoking the PrintName method."); Console::WriteLine(S"-----------------------------------------------------"); methInfo = obj->GetType()->GetMethod(S"PrintName"); Object* args3[] = {S"Brad", S"Smith"}; methInfo->Invoke(obj, static_cast<BindingFlags>(BindingFlags::IgnoreReturn | BindingFlags::InvokeMethod), 0, args3, 0); // BindingFlags::OptionalParamBinding Console::WriteLine(); Console::WriteLine(S"Using OptionalParamBinding and invoking the PrintName method."); Console::WriteLine(S"-------------------------------------------------------------"); methInfo = obj->GetType()->GetMethod(S"PrintName"); Object* args4[] = {S"Brad", S"Smith"}; methInfo->Invoke(obj, static_cast<BindingFlags>(BindingFlags::OptionalParamBinding | BindingFlags::InvokeMethod), 0, args4, 0); // BindingFlags::ExactBinding Console::WriteLine(); Console::WriteLine(S"Using ExactBinding and invoking the PrintName method."); Console::WriteLine(S"-----------------------------------------------------"); methInfo = obj->GetType()->GetMethod(S"PrintName"); Object* args5[] = {S"Brad", S"Smith"}; methInfo->Invoke(obj, static_cast<BindingFlags>(BindingFlags::ExactBinding | BindingFlags::InvokeMethod), 0, args5, 0); // BindingFlags::FlattenHierarchy Console::WriteLine(); Console::WriteLine(S"Using FlattenHierarchy and invoking the PrintName method."); Console::WriteLine(S"---------------------------------------------------------"); methInfo = obj->GetType()->GetMethod(S"PrintName"); Object* args6[] = {S"Brad", S"Smith"}; methInfo->Invoke(obj, static_cast<BindingFlags>(BindingFlags::FlattenHierarchy | BindingFlags::InvokeMethod), 0, args6, 0); } }; int main() { String* args[] = Environment::GetCommandLineArgs(); Invoke::Go(); } //}
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Requirements
Namespace: System.Reflection
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework
Assembly: Mscorlib (in Mscorlib.dll)