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System.Type.GetProperty methods

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This article provides supplementary remarks to the reference documentation for this API.

GetProperty(String) method

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 aren't inherited.

GetProperty(String, BindingFlags) method

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 or BindingFlags.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 include public and protected 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 of name.
  • 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.

GetProperty(System.String,System.Reflection.BindingFlags,System.Reflection.Binder,System.Type,System.Type[],System.Reflection.ParameterModifier[])

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.2
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.2

Notes:

  1. 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.
  2. 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.
  3. 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 or BindingFlags.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 include public and protected 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 of name.
  • 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, C#, and C++ 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.