Specifies whether the property this attribute is bound to is read-only or read/write. This class cannot be inherited
Assembly: System (in System.dll)
Thetype exposes the following members.
|Equals||Indicates whether this instance and a specified object are equal. (Overrides Attribute.Equals(Object).)|
|Finalize||Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)|
|GetHashCode||Returns the hash code for this instance. (Overrides Attribute.GetHashCode.)|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|IsDefaultAttribute||Determines if this attribute is the default. (Overrides Attribute.IsDefaultAttribute.)|
|Match||When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)|
|MemberwiseClone||Creates a shallow copy of the current Object. (Inherited from Object.)|
|ToString||Returns a string that represents the current object. (Inherited from Object.)|
|Default||Specifies the default value for the , which is No (that is, the property this attribute is bound to is read/write). This static field is read-only.|
|No||Specifies that the property this attribute is bound to is read/write and can be modified. This static field is read-only.|
|Yes||Specifies that the property this attribute is bound to is read-only and cannot be modified in the server explorer. This static field is read-only.|
|_Attribute.GetIDsOfNames||Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)|
|_Attribute.GetTypeInfo||Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)|
|_Attribute.GetTypeInfoCount||Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)|
|_Attribute.Invoke||Provides access to properties and methods exposed by an object. (Inherited from Attribute.)|
Members that are marked with the set to true or that do not have a Set method cannot be changed. Members that do not have this attribute or that are marked with the set to false are read/write, and they can be changed. The default is No.
The PropertyDescriptor class enforces the in the design environment and at run time. When you mark a property with the set to true, the value of this attribute is set to the constant member Yes. For a property marked with the set to false, the value is No. Therefore, when you want to check the value of this attribute in your code, you must specify the attribute as ReadOnlyAttribute.Yes or ReadOnlyAttribute.No.
For more information, see Extending Metadata Using Attributes.
The following code example marks a property as read-only.
The next code example shows how to check the value of the for MyProperty. First, the code gets a PropertyDescriptorCollection with all the properties for the object. Next, it indexes into the PropertyDescriptorCollection to get MyProperty. Then it returns the attributes for this property and saves them in the attributes variable.
The example presents two different ways of checking the value of the . In the second code fragment, the example calls the Equals method. In the last code fragment, the example uses the IsReadOnly property to check the value.
' Gets the attributes for the property. Dim attributes As AttributeCollection = _ TypeDescriptor.GetProperties(Me)("MyProperty").Attributes ' Checks to see whether the value of the ReadOnlyAttribute is Yes. If attributes(GetType(ReadOnlyAttribute)).Equals(ReadOnlyAttribute.Yes) Then ' Insert code here. End If ' This is another way to see whether the property is read-only. Dim myAttribute As ReadOnlyAttribute = _ CType(attributes(GetType(ReadOnlyAttribute)), ReadOnlyAttribute) If myAttribute.IsReadOnly Then ' Insert code here. End If
If you marked a class with the , use the following code example to check the value.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.