Type.GetProperty Method
Definition
Important
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Gets a specific property of the current Type.
Overloads
GetProperty(String, Type, Type[]) |
Searches for the specified public property whose parameters match the specified argument types. |
GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]) |
Searches for the specified property whose parameters match the specified argument types and modifiers, using the specified binding constraints. |
GetProperty(String, Type, Type[], ParameterModifier[]) |
Searches for the specified public property whose parameters match the specified argument types and modifiers. |
GetProperty(String, Type[]) |
Searches for the specified public property whose parameters match the specified argument types. |
GetProperty(String, Type) |
Searches for the public property with the specified name and return type. |
GetProperty(String, BindingFlags) |
Searches for the specified property, using the specified binding constraints. |
GetProperty(String) |
Searches for the public property with the specified name. |
GetProperty(String, Type, Type[])
Searches for the specified public property whose parameters match the specified argument types.
public:
System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types);
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types);
public System.Reflection.PropertyInfo? GetProperty (string name, Type? returnType, Type[] types);
public System.Reflection.PropertyInfo GetProperty (string name, Type returnType, Type[] types);
member this.GetProperty : string * Type * Type[] -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type * Type[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type * Type[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, returnType As Type, types As Type()) As PropertyInfo
Parameters
- name
- String
The string containing the name of the public property to get.
- returnType
- Type
The return type of the property.
- types
- Type[]
An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.
-or-
An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.
Returns
An object representing the public property whose parameters match the specified argument types, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name and matching the specified argument types.
types
is multidimensional.
An element of types
is null
.
Remarks
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
The search for name
is case-sensitive. The search includes public static and public instance properties.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- DefaultBinder
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)
Applies to
GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
Searches for the specified property whose parameters match the specified argument types and modifiers, using the specified binding constraints.
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, System::Reflection::BindingFlags bindingAttr, System::Reflection::Binder ^ binder, Type ^ returnType, cli::array <Type ^> ^ types, cli::array <System::Reflection::ParameterModifier> ^ modifiers);
public System.Reflection.PropertyInfo? GetProperty (string name, System.Reflection.BindingFlags bindingAttr, System.Reflection.Binder? binder, Type? returnType, Type[] types, System.Reflection.ParameterModifier[]? modifiers);
public System.Reflection.PropertyInfo GetProperty (string name, System.Reflection.BindingFlags bindingAttr, System.Reflection.Binder binder, Type returnType, Type[] types, System.Reflection.ParameterModifier[] modifiers);
abstract member GetProperty : string * System.Reflection.BindingFlags * System.Reflection.Binder * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * System.Reflection.BindingFlags * System.Reflection.Binder * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, bindingAttr As BindingFlags, binder As Binder, returnType As Type, types As Type(), modifiers As ParameterModifier()) As PropertyInfo
Parameters
- name
- String
The string containing the name of the property to get.
- bindingAttr
- BindingFlags
A bitwise combination of the enumeration values that specify how the search is conducted.
-or-
Default to return null
.
- binder
- Binder
An object that defines a set of properties and enables binding, which can involve selection of an overloaded method, coercion of argument types, and invocation of a member through reflection.
-or-
A null reference (Nothing
in Visual Basic), to use the DefaultBinder.
- returnType
- Type
The return type of the property.
- types
- Type[]
An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.
-or-
An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.
- modifiers
- ParameterModifier[]
An array of ParameterModifier objects representing the attributes associated with the corresponding element in the types
array. The default binder does not process this parameter.
Returns
An object representing the property that matches the specified requirements, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name and matching the specified binding constraints.
types
is multidimensional.
-or-
modifiers
is multidimensional.
-or-
types
and modifiers
do not have the same length.
An element of types
is null
.
Remarks
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
Although the default binder does not process ParameterModifier (the modifiers
parameter), you can use the abstract System.Reflection.Binder class to write a custom binder that does process modifiers
. ParameterModifier
is only used when calling through COM interop, and only parameters that are passed by reference are handled.
The following table shows what members of a base class are returned by the Get
methods when reflecting on a type.
Member Type | Static | Non-Static |
---|---|---|
Constructor | No | No |
Field | No | Yes. A field is always hide-by-name-and-signature. |
Event | Not applicable | The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below. |
Method | No | Yes. A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature. |
Nested Type | No | No |
Property | Not applicable | The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below. |
Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.
For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.
Custom attributes are not part of the common type system.
The following BindingFlags filter flags can be used to define which properties to include in the search:
You must specify either
BindingFlags.Instance
orBindingFlags.Static
in order to get a return.Specify
BindingFlags.Public
to include public properties in the search.Specify
BindingFlags.NonPublic
to include non-public properties (that is, private, internal, and protected properties) in the search.Specify
BindingFlags.FlattenHierarchy
to includepublic
andprotected
static members up the hierarchy;private
static members in inherited classes are not included.
The following BindingFlags modifier flags can be used to change how the search works:
BindingFlags.IgnoreCase
to ignore the case ofname
.BindingFlags.DeclaredOnly
to search only the properties declared on the Type, not properties that were simply inherited.
See System.Reflection.BindingFlags for more information.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- BindingFlags
- Binder
- DefaultBinder
- ParameterModifier
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)
Applies to
GetProperty(String, Type, Type[], ParameterModifier[])
Searches for the specified public property whose parameters match the specified argument types and modifiers.
public:
System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types, cli::array <System::Reflection::ParameterModifier> ^ modifiers);
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType, cli::array <Type ^> ^ types, cli::array <System::Reflection::ParameterModifier> ^ modifiers);
public System.Reflection.PropertyInfo? GetProperty (string name, Type? returnType, Type[] types, System.Reflection.ParameterModifier[]? modifiers);
public System.Reflection.PropertyInfo GetProperty (string name, Type returnType, Type[] types, System.Reflection.ParameterModifier[] modifiers);
member this.GetProperty : string * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type * Type[] * System.Reflection.ParameterModifier[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, returnType As Type, types As Type(), modifiers As ParameterModifier()) As PropertyInfo
Parameters
- name
- String
The string containing the name of the public property to get.
- returnType
- Type
The return type of the property.
- types
- Type[]
An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.
-or-
An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.
- modifiers
- ParameterModifier[]
An array of ParameterModifier objects representing the attributes associated with the corresponding element in the types
array. The default binder does not process this parameter.
Returns
An object representing the public property that matches the specified requirements, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name and matching the specified argument types and modifiers.
types
is multidimensional.
-or-
modifiers
is multidimensional.
-or-
types
and modifiers
do not have the same length.
An element of types
is null
.
Examples
The following example obtains a Type
object corresponding to MyPropertyClass
, and the indexed property of this class is retrieved using the arguments passed to the GetProperty
method.
using namespace System;
using namespace System::Reflection;
public ref class MyPropertyClass
{
private:
array<int, 2>^ myPropertyArray;
public:
property int Item [int, int]
{
// Declare an indexer.
int get( int i, int j )
{
return myPropertyArray[ i,j ];
}
void set( int i, int j, int value )
{
myPropertyArray[ i,j ] = value;
}
}
};
int main()
{
try
{
Type^ myType = MyPropertyClass::typeid;
array<Type^>^myTypeArray = gcnew array<Type^>(2);
// Create an instance of the Type array representing the number, order
// and type of the parameters for the property.
myTypeArray->SetValue( int::typeid, 0 );
myTypeArray->SetValue( int::typeid, 1 );
// Search for the indexed property whose parameters match the
// specified argument types and modifiers.
PropertyInfo^ myPropertyInfo = myType->GetProperty( "Item", int::typeid, myTypeArray, nullptr );
Console::WriteLine( "{0}.{1} has a property type of {2}", myType->FullName, myPropertyInfo->Name, myPropertyInfo->PropertyType );
}
catch ( Exception^ ex )
{
Console::WriteLine( "An exception occurred {0}", ex->Message );
}
}
using System;
using System.Reflection;
public class MyPropertyClass
{
private int [,] myPropertyArray = new int[10,10];
// Declare an indexer.
public int this [int i,int j]
{
get
{
return myPropertyArray[i,j];
}
set
{
myPropertyArray[i,j] = value;
}
}
}
public class MyTypeClass
{
public static void Main()
{
try
{
Type myType=typeof(MyPropertyClass);
Type[] myTypeArray = new Type[2];
// Create an instance of the Type array representing the number, order
// and type of the parameters for the property.
myTypeArray.SetValue(typeof(int),0);
myTypeArray.SetValue(typeof(int),1);
// Search for the indexed property whose parameters match the
// specified argument types and modifiers.
PropertyInfo myPropertyInfo = myType.GetProperty("Item",
typeof(int),myTypeArray,null);
Console.WriteLine(myType.FullName + "." + myPropertyInfo.Name +
" has a property type of " + myPropertyInfo.PropertyType);
}
catch(Exception ex)
{
Console.WriteLine("An exception occurred " + ex.Message);
}
}
}
open System
type MyPropertyClass() =
let myPropertyArray = Array2D.zeroCreate<int> 10 10
// Declare an indexed property.
member _.Item
with get (i, j) =
myPropertyArray[i, j]
and set (i, j) value =
myPropertyArray[i, j] <- value
try
let myType = typeof<MyPropertyClass>
let myTypeArray = Array.zeroCreate<Type> 2
// Create an instance of the Type array representing the number, order
// and type of the parameters for the property.
myTypeArray.SetValue(typeof<int>, 0)
myTypeArray.SetValue(typeof<int>, 1)
// Search for the indexed property whose parameters match the
// specified argument types and modifiers.
let myPropertyInfo = myType.GetProperty("Item", typeof<int>, myTypeArray, null)
printfn $"{myType.FullName}.{myPropertyInfo.Name} has a property type of {myPropertyInfo.PropertyType}"
with ex ->
printfn $"An exception occurred {ex.Message}"
Imports System.Reflection
Public Class MyPropertyClass
Private myPropertyArray(9, 9) As Integer
' Declare an indexer.
Default Public Property Item(ByVal i As Integer, ByVal j As Integer) As Integer
Get
Return myPropertyArray(i, j)
End Get
Set(ByVal Value As Integer)
myPropertyArray(i, j) = Value
End Set
End Property
End Class
Public Class MyTypeClass
Public Shared Sub Main()
Try
Dim myType As Type = GetType(MyPropertyClass)
Dim myTypeArray(1) As Type
' Create an instance of a Type array representing the number, order
' and type of the parameters for the property.
myTypeArray.SetValue(GetType(Integer), 0)
myTypeArray.SetValue(GetType(Integer), 1)
' Search for the indexed property whose parameters match the
' specified argument types and modifiers.
Dim myPropertyInfo As PropertyInfo = myType.GetProperty("Item", _
GetType(Integer), myTypeArray, Nothing)
Console.WriteLine(myType.FullName + "." + myPropertyInfo.Name + _
" has a property type of " + myPropertyInfo.PropertyType.ToString())
Catch ex As Exception
Console.WriteLine("An exception occurred " + ex.Message.ToString())
End Try
End Sub
End Class
Remarks
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
Although the default binder does not process ParameterModifier (the modifiers
parameter), you can use the abstract System.Reflection.Binder class to write a custom binder that does process modifiers
. ParameterModifier
is only used when calling through COM interop, and only parameters that are passed by reference are handled.
The search for name
is case-sensitive. The search includes public static and public instance properties.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- DefaultBinder
- ParameterModifier
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)
Applies to
GetProperty(String, Type[])
Searches for the specified public property whose parameters match the specified argument types.
public:
System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, cli::array <Type ^> ^ types);
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, cli::array <Type ^> ^ types);
public System.Reflection.PropertyInfo? GetProperty (string name, Type[] types);
public System.Reflection.PropertyInfo GetProperty (string name, Type[] types);
member this.GetProperty : string * Type[] -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type[] -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type[] -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, types As Type()) As PropertyInfo
Parameters
- name
- String
The string containing the name of the public property to get.
- types
- Type[]
An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.
-or-
An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.
Returns
An object representing the public property whose parameters match the specified argument types, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name and matching the specified argument types.
types
is multidimensional.
An element of types
is null
.
Examples
The following example retrieves the Type
object of a user-defined class, retrieves the property of that class, and displays the property name and type of the property as specified by the arguments passed to GetProperty
.
using namespace System;
using namespace System::Reflection;
ref class MyClass1
{
private:
array<int, 2>^myArray;
public:
property int Item [int, int]
{
// Declare an indexer.
int get( int i, int j )
{
return myArray[ i,j ];
}
void set( int i, int j, int value )
{
myArray[ i,j ] = value;
}
}
};
int main()
{
try
{
// Get the Type object.
Type^ myType = MyClass1::typeid;
array<Type^>^myTypeArr = gcnew array<Type^>(2);
// Create an instance of a Type array.
myTypeArr->SetValue( int::typeid, 0 );
myTypeArr->SetValue( int::typeid, 1 );
// Get the PropertyInfo object for the indexed property Item, which has two integer parameters.
PropertyInfo^ myPropInfo = myType->GetProperty( "Item", myTypeArr );
// Display the property.
Console::WriteLine( "The {0} property exists in MyClass1.", myPropInfo );
}
catch ( NullReferenceException^ e )
{
Console::WriteLine( "An exception occurred." );
Console::WriteLine( "Source : {0}", e->Source );
Console::WriteLine( "Message : {0}", e->Message );
}
}
using System;
using System.Reflection;
class MyClass1
{
private int [,] myArray = {{1,2},{3,4}};
// Declare an indexer.
public int this [int i,int j]
{
get
{
return myArray[i,j];
}
set
{
myArray[i,j] = value;
}
}
}
public class MyTypeClass
{
public static void Main(string[] args)
{
try
{
// Get the Type object.
Type myType=typeof(MyClass1);
Type[] myTypeArr = new Type[2];
// Create an instance of a Type array.
myTypeArr.SetValue(typeof(int),0);
myTypeArr.SetValue(typeof(int),1);
// Get the PropertyInfo object for the indexed property Item, which has two integer parameters.
PropertyInfo myPropInfo = myType.GetProperty("Item", myTypeArr);
// Display the property.
Console.WriteLine("The {0} property exists in MyClass1.", myPropInfo.ToString());
}
catch(NullReferenceException e)
{
Console.WriteLine("An exception occurred.");
Console.WriteLine("Source : {0}" , e.Source);
Console.WriteLine("Message : {0}" , e.Message);
}
}
}
open System
type MyClass1() =
let myArray = array2D [[1; 2]; [3; 4]]
// Declare an indexed property.
member _.Item
with get (i, j) =
myArray[i, j]
and set (i, j) value =
myArray[i, j] <- value
try
// Get the Type object.
let myType = typeof<MyClass1>
let myTypeArr = Array.zeroCreate<Type> 2
// Create an instance of a Type array.
myTypeArr.SetValue(typeof<int>, 0)
myTypeArr.SetValue(typeof<int>, 1)
// Get the PropertyInfo object for the indexed property Item, which has two integer parameters.
let myPropInfo = myType.GetProperty("Item", myTypeArr)
// Display the property.
printfn $"The {myPropInfo} property exists in MyClass1."
with :? NullReferenceException as e ->
printfn "An exception occurred."
printfn $"Source : {e.Source}"
printfn $"Message : {e.Message}"
Imports System.Reflection
Module Module1
Class MyClass1
Private myArray As Integer(,) = {{1, 2}, {3, 4}}
' Declare an indexer.
Default Public Property Item(ByVal i As Integer, ByVal j As Integer) As Integer
Get
Return myArray(i, j)
End Get
Set(ByVal Value As Integer)
myArray(i, j) = Value
End Set
End Property
End Class
Public Class MyTypeClass
Public Shared Sub Main()
Try
' Get the Type Object.
Dim myType As Type = GetType(MyClass1)
Dim myTypeArr(1) As Type
' Create an instance of a Type array.
myTypeArr.SetValue(GetType(Integer), 0)
myTypeArr.SetValue(GetType(Integer), 1)
' Get the PropertyInfo object for the indexed property Item, which has two integer parameters.
Dim myPropInfo As PropertyInfo = myType.GetProperty("Item", myTypeArr)
' Display the property.
Console.WriteLine("The {0} property exists in MyClass1.", myPropInfo.ToString())
Catch e As NullReferenceException
Console.WriteLine("An exception occurred.")
Console.WriteLine("Source : {0}", e.Source.ToString())
Console.WriteLine("Message : {0}", e.Message.ToString())
End Try
End Sub
End Class
End Module 'Module1
Remarks
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
The search for name
is case-sensitive. The search includes public static and public instance properties.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- DefaultBinder
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)
Applies to
GetProperty(String, Type)
Searches for the public property with the specified name and return type.
public:
System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType);
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, Type ^ returnType);
public System.Reflection.PropertyInfo? GetProperty (string name, Type? returnType);
public System.Reflection.PropertyInfo GetProperty (string name, Type returnType);
member this.GetProperty : string * Type -> System.Reflection.PropertyInfo
abstract member GetProperty : string * Type -> System.Reflection.PropertyInfo
override this.GetProperty : string * Type -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, returnType As Type) As PropertyInfo
Parameters
- name
- String
The string containing the name of the public property to get.
- returnType
- Type
The return type of the property.
Returns
An object representing the public property with the specified name, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name.
name
is null
, or returnType
is null
.
Examples
The following example defines a class with one property and retrieves the name and type of the property.
using namespace System;
using namespace System::Reflection;
ref class MyClass1
{
private:
String^ myMessage;
public:
property String^ MyProperty1
{
String^ get()
{
return myMessage;
}
void set( String^ value )
{
myMessage = value;
}
}
};
int main()
{
try
{
Type^ myType = MyClass1::typeid;
// Get the PropertyInfo Object* representing MyProperty1.
PropertyInfo^ myStringProperties1 = myType->GetProperty( "MyProperty1", String::typeid );
Console::WriteLine( "The name of the first property of MyClass1 is {0}.", myStringProperties1->Name );
Console::WriteLine( "The type of the first property of MyClass1 is {0}.", myStringProperties1->PropertyType );
}
catch ( ArgumentNullException^ e )
{
Console::WriteLine( "ArgumentNullException : {0}", e->Message );
}
catch ( AmbiguousMatchException^ e )
{
Console::WriteLine( "AmbiguousMatchException : {0}", e->Message );
}
catch ( NullReferenceException^ e )
{
Console::WriteLine( "Source : {0}", e->Source );
Console::WriteLine( "Message : {0}", e->Message );
}
//Output:
//The name of the first property of MyClass1 is MyProperty1.
//The type of the first property of MyClass1 is System.String.
}
using System;
using System.Reflection;
class MyClass1
{
String myMessage="Hello World.";
public string MyProperty1
{
get
{
return myMessage;
}
set
{
myMessage =value;
}
}
}
class TestClass
{
static void Main()
{
try
{
Type myType = typeof(MyClass1);
// Get the PropertyInfo object representing MyProperty1.
PropertyInfo myStringProperties1 = myType.GetProperty("MyProperty1",
typeof(string));
Console.WriteLine("The name of the first property of MyClass1 is {0}.", myStringProperties1.Name);
Console.WriteLine("The type of the first property of MyClass1 is {0}.", myStringProperties1.PropertyType);
}
catch(ArgumentNullException e)
{
Console.WriteLine("ArgumentNullException :"+e.Message);
}
catch(AmbiguousMatchException e)
{
Console.WriteLine("AmbiguousMatchException :"+e.Message);
}
catch(NullReferenceException e)
{
Console.WriteLine("Source : {0}" , e.Source);
Console.WriteLine("Message : {0}" , e.Message);
}
//Output:
//The name of the first property of MyClass1 is MyProperty1.
//The type of the first property of MyClass1 is System.String.
}
}
open System
open System.Reflection
type MyClass1() =
let mutable myMessage = "Hello World."
member _.MyProperty1
with get () =
myMessage
and set (value) =
myMessage <- value
try
let myType = typeof<MyClass1>
// Get the PropertyInfo object representing MyProperty1.
let myStringProperties1 = myType.GetProperty("MyProperty1", typeof<string>)
printfn $"The name of the first property of MyClass1 is {myStringProperties1.Name}."
printfn $"The type of the first property of MyClass1 is {myStringProperties1.PropertyType}."
with
| :? ArgumentNullException as e ->
printfn $"ArgumentNullException :{e.Message}"
| :? AmbiguousMatchException as e ->
printfn $"AmbiguousMatchException :{e.Message}"
| :? NullReferenceException as e ->
printfn $"Source : {e.Source}"
printfn $"Message : {e.Message}"
// Output:
// The name of the first property of MyClass1 is MyProperty1.
// The type of the first property of MyClass1 is System.String.
Imports System.Reflection
Class MyClass1
Private myMessage As [String] = "Hello World."
Public Property MyProperty1() As String
Get
Return myMessage
End Get
Set(ByVal Value As String)
myMessage = Value
End Set
End Property
End Class
Class TestClass
Shared Sub Main()
Try
Dim myType As Type = GetType(MyClass1)
' Get the PropertyInfo object representing MyProperty1.
Dim myStringProperties1 As PropertyInfo = myType.GetProperty("MyProperty1", GetType(String))
Console.WriteLine("The name of the first property of MyClass1 is {0}.", myStringProperties1.Name)
Console.WriteLine("The type of the first property of MyClass1 is {0}.", myStringProperties1.PropertyType.ToString())
Catch e As ArgumentNullException
Console.WriteLine("ArgumentNullException :" + e.Message.ToString())
Catch e As AmbiguousMatchException
Console.WriteLine("AmbiguousMatchException :" + e.Message.ToString())
Catch e As NullReferenceException
Console.WriteLine("Source : {0}", e.Source.ToString())
Console.WriteLine("Message : {0}", e.Message.ToString())
End Try
'Output:
'The name of the first property of MyClass1 is MyProperty1.
'The type of the first property of MyClass1 is System.String.
End Sub
End Class
Remarks
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
The search for name
is case-sensitive. The search includes public static and public instance properties.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- DefaultBinder
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)
Applies to
GetProperty(String, BindingFlags)
Searches for the specified property, using the specified binding constraints.
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name, System::Reflection::BindingFlags bindingAttr);
public System.Reflection.PropertyInfo? GetProperty (string name, System.Reflection.BindingFlags bindingAttr);
public System.Reflection.PropertyInfo GetProperty (string name, System.Reflection.BindingFlags bindingAttr);
abstract member GetProperty : string * System.Reflection.BindingFlags -> System.Reflection.PropertyInfo
override this.GetProperty : string * System.Reflection.BindingFlags -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String, bindingAttr As BindingFlags) As PropertyInfo
Parameters
- name
- String
The string containing the name of the property to get.
- bindingAttr
- BindingFlags
A bitwise combination of the enumeration values that specify how the search is conducted.
-or-
Default to return null
.
Returns
An object representing the property that matches the specified requirements, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name and matching the specified binding constraints.
name
is null
.
Examples
The following example retrieves the type of a user-defined class, retrieves a property of that class and displays the property name in accordance with the specified binding constraints.
using namespace System;
using namespace System::Reflection;
ref class MyClass
{
private:
int myProperty;
public:
property int MyProperty
{
// Declare MyProperty.
int get()
{
return myProperty;
}
void set( int value )
{
myProperty = value;
}
}
};
int main()
{
try
{
// Get Type object of MyClass.
Type^ myType = MyClass::typeid;
// Get the PropertyInfo by passing the property name and specifying the BindingFlags.
PropertyInfo^ myPropInfo = myType->GetProperty( "MyProperty", static_cast<BindingFlags>(BindingFlags::Public | BindingFlags::Instance) );
// Display Name propety to console.
Console::WriteLine( "{0} is a property of MyClass.", myPropInfo->Name );
}
catch ( NullReferenceException^ e )
{
Console::WriteLine( "MyProperty does not exist in MyClass. {0}", e->Message );
}
}
using System;
using System.Reflection;
class MyClass
{
private int myProperty;
// Declare MyProperty.
public int MyProperty
{
get
{
return myProperty;
}
set
{
myProperty=value;
}
}
}
public class MyTypeClass
{
public static void Main(string[] args)
{
try
{
// Get Type object of MyClass.
Type myType=typeof(MyClass);
// Get the PropertyInfo by passing the property name and specifying the BindingFlags.
PropertyInfo myPropInfo = myType.GetProperty("MyProperty", BindingFlags.Public | BindingFlags.Instance);
// Display Name propety to console.
Console.WriteLine("{0} is a property of MyClass.", myPropInfo.Name);
}
catch(NullReferenceException e)
{
Console.WriteLine("MyProperty does not exist in MyClass." +e.Message);
}
}
}
open System
open System.Reflection
type MyClass() =
let mutable myProperty = 0
// Declare MyProperty.
member _.MyProperty
with get () =
myProperty
and set (value) =
myProperty <- value
try
// Get Type object of MyClass.
let myType = typeof<MyClass>
// Get the PropertyInfo by passing the property name and specifying the BindingFlags.
let myPropInfo = myType.GetProperty("MyProperty", BindingFlags.Public ||| BindingFlags.Instance)
// Display Name propety to console.
printfn $"{myPropInfo.Name} is a property of MyClass."
with :? NullReferenceException as e ->
printfn $"MyProperty does not exist in MyClass.{e.Message}"
Imports System.Reflection
Module Module1
Public Class MyClass1
Private myProperty1 As Integer
' Declare MyProperty.
Public Property MyProperty() As Integer
Get
Return myProperty1
End Get
Set(ByVal Value As Integer)
myProperty1 = Value
End Set
End Property
Public Shared Sub Main()
Try
' Get a Type object corresponding to MyClass.
Dim myType As Type = GetType(MyClass1)
' Get a PropertyInfo object by passing property name and specifying BindingFlags.
Dim myPropInfo As PropertyInfo = myType.GetProperty("MyProperty", BindingFlags.Public Or BindingFlags.Instance)
' Display the Name property.
Console.WriteLine("{0} is a property of MyClass.", myPropInfo.Name)
Catch e As NullReferenceException
Console.WriteLine("MyProperty does not exist in MyClass.", e.Message.ToString())
End Try
End Sub
End Class
End Module 'Module1
Remarks
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
The following BindingFlags filter flags can be used to define which properties to include in the search:
You must specify either
BindingFlags.Instance
orBindingFlags.Static
in order to get a return.Specify
BindingFlags.Public
to include public properties in the search.Specify
BindingFlags.NonPublic
to include non-public properties (that is, private, internal, and protected properties) in the search.Specify
BindingFlags.FlattenHierarchy
to includepublic
andprotected
static members up the hierarchy;private
static members in inherited classes are not included.
The following BindingFlags modifier flags can be used to change how the search works:
BindingFlags.IgnoreCase
to ignore the case ofname
.BindingFlags.DeclaredOnly
to search only the properties declared on the Type, not properties that were simply inherited.
See System.Reflection.BindingFlags for more information.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Situations in which AmbiguousMatchException occurs include the following:
A type contains two indexed properties that have the same name but different numbers of parameters. To resolve the ambiguity, use an overload of the GetProperty method that specifies parameter types.
A derived type declares a property that hides an inherited property with the same name, using the
new
modifier (Shadows
in Visual Basic). To resolve the ambiguity, include BindingFlags.DeclaredOnly to restrict the search to members that are not inherited.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- BindingFlags
- DefaultBinder
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)
Applies to
GetProperty(String)
Searches for the public property with the specified name.
public:
System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name);
public:
virtual System::Reflection::PropertyInfo ^ GetProperty(System::String ^ name);
public System.Reflection.PropertyInfo? GetProperty (string name);
public System.Reflection.PropertyInfo GetProperty (string name);
member this.GetProperty : string -> System.Reflection.PropertyInfo
abstract member GetProperty : string -> System.Reflection.PropertyInfo
override this.GetProperty : string -> System.Reflection.PropertyInfo
Public Function GetProperty (name As String) As PropertyInfo
Parameters
- name
- String
The string containing the name of the public property to get.
Returns
An object representing the public property with the specified name, if found; otherwise, null
.
Implements
Exceptions
More than one property is found with the specified name.
name
is null
.
Examples
The following example retrieves the Type
object of a user-defined class, retrieves a property of that class, and displays the property name.
using namespace System;
using namespace System::Reflection;
ref class MyClass
{
private:
int myProperty;
public:
property int MyProperty
{
// Declare MyProperty.
int get()
{
return myProperty;
}
void set( int value )
{
myProperty = value;
}
}
};
int main()
{
try
{
// Get the Type object corresponding to MyClass.
Type^ myType = MyClass::typeid;
// Get the PropertyInfo object by passing the property name.
PropertyInfo^ myPropInfo = myType->GetProperty( "MyProperty" );
// Display the property name.
Console::WriteLine( "The {0} property exists in MyClass.", myPropInfo->Name );
}
catch ( NullReferenceException^ e )
{
Console::WriteLine( "The property does not exist in MyClass. {0}", e->Message );
}
}
using System;
using System.Reflection;
class MyClass
{
private int myProperty;
// Declare MyProperty.
public int MyProperty
{
get
{
return myProperty;
}
set
{
myProperty=value;
}
}
}
public class MyTypeClass
{
public static void Main(string[] args)
{
try
{
// Get the Type object corresponding to MyClass.
Type myType=typeof(MyClass);
// Get the PropertyInfo object by passing the property name.
PropertyInfo myPropInfo = myType.GetProperty("MyProperty");
// Display the property name.
Console.WriteLine("The {0} property exists in MyClass.", myPropInfo.Name);
}
catch(NullReferenceException e)
{
Console.WriteLine("The property does not exist in MyClass." + e.Message);
}
}
}
open System
type MyClass() =
let mutable myProperty = 0
// Declare MyProperty.
member _.MyProperty
with get () =
myProperty
and set (value) =
myProperty <- value
try
// Get the Type object corresponding to MyClass.
let myType = typeof<MyClass>
// Get the PropertyInfo object by passing the property name.
let myPropInfo = myType.GetProperty "MyProperty"
// Display the property name.
printfn $"The {myPropInfo.Name} property exists in MyClass."
with :? NullReferenceException as e ->
printfn $"The property does not exist in MyClass.{e.Message}"
Imports System.Reflection
Class MyClass1
Private myProperty1 As Integer
' Declare MyProperty.
Public Property MyProperty() As Integer
Get
Return myProperty1
End Get
Set(ByVal Value As Integer)
myProperty1 = Value
End Set
End Property
End Class
Public Class MyTypeClass
Public Shared Sub Main(ByVal args() As String)
Try
' Get Type Object corresponding to MyClass.
Dim myType As Type = GetType(MyClass1)
' Get PropertyInfo object by passing property name.
Dim myPropInfo As PropertyInfo = myType.GetProperty("MyProperty")
' Display Name propety to console.
Console.WriteLine("The {0} property exists in MyClass.", myPropInfo.Name)
Catch e As NullReferenceException
Console.WriteLine("The property does not exist in MyClass.", e.Message.ToString())
End Try
End Sub
End Class
Internally, this property is referred to in the metadata by the name "Item." Any attempt to get PropertyInfo
using reflection must specify this internal name in order to correctly return the PropertyInfo
property.
Remarks
The search for name
is case-sensitive. The search includes public static and public instance properties.
A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or
) to get it.
If the current Type represents a constructed generic type, this method returns the PropertyInfo with the type parameters replaced by the appropriate type arguments.
If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the properties of the class constraint.
Situations in which AmbiguousMatchException occurs include the following:
A type contains two indexed properties that have the same name but different numbers of parameters. To resolve the ambiguity, use an overload of the GetProperty method that specifies parameter types.
A derived type declares a property that hides an inherited property with the same name, by using the
new
modifier (Shadows
in Visual Basic). To resolve the ambiguity, use the GetProperty(String, BindingFlags) method overload and add the BindingFlags.DeclaredOnly flag to restrict the search to members that are not inherited.
Indexers and Default Properties
Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList
refers to an ArrayList, the syntax myList[3]
(myList(3)
in Visual Basic) retrieves the element with the index of 3. You can overload the property.
In C#, this feature is called an indexer and cannot be referred to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars[]. Indexed properties created using languages other than C# can have names other than Item, as well.
To determine whether a type has a default property, use the GetCustomAttributes(Type, Boolean) method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.
See also
- PropertyInfo
- String
- DefaultBinder
- GetPropertyImpl(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])
- GetProperties(BindingFlags)