Allows you to obtain the method or property name of the caller to the method.
Assembly: mscorlib (in mscorlib.dll)
Thetype exposes the following members.
|Equals||Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)|
|GetHashCode||Returns the hash code for this instance. (Inherited from Attribute.)|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|IsDefaultAttribute||When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)|
|Match||When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)|
|ToString||Returns a string that represents the current object. (Inherited from Object.)|
|_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.)|
You apply the CallerMemberName attribute to an optional parameter that has a default value. You must specify an explicit default value for the optional parameter. You can't apply this attribute to parameters that aren't specified as optional.
For more information, see Caller Information (C# and Visual Basic).
You can use the CallerMemberName attribute to avoid specifying the member name as a String argument to the called method. By using this technique, you avoid the problem that Rename Refactoring doesn't change the String values. This is especially useful for the following tasks:
Using tracing and diagnostic routines.
Implementing the INotifyPropertyChanged interface when binding data. This interface allows the property of an object to notify a bound control that the property has changed, so that the control can display the updated information. Without the CallerMemberName attribute, you must specify the property name as a literal.
The following chart shows the member names that are returned when you use the CallerMemberName attribute.
Call occurs within
Member name result
Method, property, or event
The name of the method, property, or event from which the call originated.
The string ".ctor"
The string ".cctor"
The string "Finalize"
User-defined operators or conversions
The generated name for the member, for example, "op_Addition".
The name of the member to which the attribute is applied. If the attribute is any element within a member (such as a parameter, a return value, or a generic type parameter), this result is the name of the member that's associated with that element.
No containing member (for example, assembly-level or attributes applied to types)
The default value of the optional parameter.
The following example shows how to use the CallerMemberName attribute. On each call to the TraceMessage method, the caller information is substituted as an argument to the optional parameter.
Private Sub DoProcessing() TraceMessage("Something happened.") End Sub Public Sub TraceMessage(message As String, <System.Runtime.CompilerServices.CallerMemberName> Optional memberName As String = Nothing, <System.Runtime.CompilerServices.CallerFilePath> Optional sourcefilePath As String = Nothing, <System.Runtime.CompilerServices.CallerLineNumber()> Optional sourceLineNumber As Integer = 0) System.Diagnostics.Trace.WriteLine("message: " & message) System.Diagnostics.Trace.WriteLine("member name: " & memberName) System.Diagnostics.Trace.WriteLine("source file path: " & sourcefilePath) System.Diagnostics.Trace.WriteLine("source line number: " & sourceLineNumber) End Sub ' Sample output: ' message: Something happened. ' member name: DoProcessing ' source file path: C:\Users\username\Documents\Visual Studio 2012\Projects\CallerInfoVB\CallerInfoVB\Form1.vb ' source line number: 15