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Control.OnDoubleClick Method

Raises the DoubleClick event.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

'Declaration
Protected Overridable Sub OnDoubleClick ( _
	e As EventArgs _
)
'Usage
Dim e As EventArgs 

Me.OnDoubleClick(e)

Parameters

e
Type: System.EventArgs

An EventArgs that contains the event data.

Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.

The OnDoubleClick method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors:

When overriding OnDoubleClick in a derived class, be sure to call the base class's OnDoubleClick method so that registered delegates receive the event.

The following code example uses the DoubleClick event of a ListBox to load text files listed in the ListBox into a TextBox control.

' This example uses the DoubleClick event of a ListBox to load text files   
' listed in the ListBox into a TextBox control. This example 
' assumes that the ListBox, named listBox1, contains a list of valid file  
' names with path and that this event handler method 
' is connected to the DoublClick event of a ListBox control named listBox1. 
' This example requires code access permission to access files. 
Private Sub listBox1_DoubleClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles listBox1.DoubleClick
    ' Get the name of the file to open from the ListBox. 
    Dim file As [String] = listBox1.SelectedItem.ToString()

    Try 
        ' Determine if the file exists before loading. 
        If System.IO.File.Exists(file) Then 
            ' Open the file and use a TextReader to read the contents into the TextBox. 
            Dim myFile As New System.IO.FileInfo(listBox1.SelectedItem.ToString())
            Dim myData As System.IO.TextReader = myFile.OpenText()

            textBox1.Text = myData.ReadToEnd()
            myData.Close()
        End If 
        ' Exception is thrown by the OpenText method of the FileInfo class. 
    Catch
        MessageBox.Show("The file you specified does not exist.")
        ' Exception is thrown by the ReadToEnd method of the TextReader class. 
    Catch
     MessageBox.Show("There was a problem loading the file into the TextBox. Ensure that the file is a valid text file.")
    End Try 
End Sub

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0
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