EventArgs.Empty Field
.NET Framework (current version)
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Provides a value to use with events that do not have event data.
Assembly: mscorlib (in mscorlib.dll)
Pass this value to event handlers that are associated with events that do not have data.
The following example shows a simple counting application that raises an event when a threshold is equaled or exceeded. The Empty field is passed to the OnThresholdReached method.
Module Module1 Sub Main() Dim c As Counter = New Counter(New Random().Next(10)) AddHandler c.ThresholdReached, AddressOf c_ThresholdReached Console.WriteLine("press 'a' key to increase total") While Console.ReadKey(True).KeyChar = "a" Console.WriteLine("adding one") c.Add(1) End While End Sub Sub c_ThresholdReached(sender As Object, e As EventArgs) Console.WriteLine("The threshold was reached.") Environment.Exit(0) End Sub End Module Class Counter Private threshold As Integer Private total As Integer Public Sub New(passedThreshold As Integer) threshold = passedThreshold End Sub Public Sub Add(x As Integer) total = total + x If (total >= threshold) Then OnThresholdReached(EventArgs.Empty) End If End Sub Protected Overridable Sub OnThresholdReached(e As EventArgs) RaiseEvent ThresholdReached(Me, e) End Sub Public Event ThresholdReached As EventHandler End Class
Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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