Key Event Handler in VB.NET

In this article we will learn how to use Key Event handler.
  • 2519
 

Determine whether user pressed Enter key

1.Open visual studio and create a project in vb.net

2.Use the following code in form1.vb

Imports System.Windows.Forms
Public Class KeyCodeEnter
    Public Shared Sub Main()
        Application.Run(New FrmFileTest)
    End Sub

End
Class
Public
Class FrmFileTest
    Inherits Form
     ' label that gives directions to user
    Friend WithEvents lblDirections As Label
     ' text boxes for inputting and outputting data
    Friend WithEvents txtOutput As TextBox
    Friend WithEvents txtInput As TextBox

#Region
" Windows Form Designer generated code "
 
    Public Sub New()
        MyBase.New()
         'This call is required by the Windows Form Designer.
        InitializeComponent()
        'Add any initialization after the InitializeComponent() call

 
    End Sub
 
    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

 
    'Required by the Windows Form Designer
    Private components As System.ComponentModel.Container
     'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer. 
    'Do not modify it using the code editor.
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.lblDirections = New System.Windows.Forms.Label()
        Me.txtOutput = New System.Windows.Forms.TextBox()
        Me.txtInput = New System.Windows.Forms.TextBox()
        Me.SuspendLayout()
        '
        'lblDirections
        '
        Me.lblDirections.Font = New System.Drawing.Font("Microsoft Sans Serif", 10.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.lblDirections.Location = New System.Drawing.Point(20, 20)
        Me.lblDirections.Name = "lblDirections"
        Me.lblDirections.Size = New System.Drawing.Size(410, 19)
        Me.lblDirections.TabIndex = 2
        Me.lblDirections.Text = "Press Enter key:"
        Me.lblDirections.TextAlign = System.Drawing.ContentAlignment.MiddleLeft
        '
        'txtOutput
        '
        Me.txtOutput.AutoSize = False
        Me.txtOutput.BackColor = System.Drawing.SystemColors.Control
        Me.txtOutput.Font = New System.Drawing.Font("Microsoft Sans Serif", 10.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.txtOutput.Location = New System.Drawing.Point(20, 109)
        Me.txtOutput.Multiline = True
        Me.txtOutput.Name = "txtOutput"
        Me.txtOutput.ReadOnly = True
        Me.txtOutput.ScrollBars = System.Windows.Forms.ScrollBars.Vertical
        Me.txtOutput.Size = New System.Drawing.Size(410, 345)
        Me.txtOutput.TabIndex = 1
        Me.txtOutput.Text = ""
        '
        'txtInput
        '
        Me.txtInput.Font = New System.Drawing.Font("Microsoft Sans Serif", 10.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
        Me.txtInput.Location = New System.Drawing.Point(20, 59)
        Me.txtInput.Name = "txtInput"
        Me.txtInput.Size = New System.Drawing.Size(410, 26)
        Me.txtInput.TabIndex = 0
        Me.txtInput.Text = ""
        '
        'FrmFileTest
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
        Me.ClientSize = New System.Drawing.Size(460, 470)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.txtOutput, Me.lblDirections, Me.txtInput})
        Me.Name = "FrmFileTest"
        Me.Text = "File Test"
        Me.ResumeLayout(False)
    End Sub

#End
Region
 
    ' invoked when user presses key
    Protected Sub txtInput_KeyDown(ByVal sender As Object, _
       ByVal e As System.Windows.Forms.KeyEventArgs) Handles _
       txtInput.KeyDown
         If e.KeyCode = Keys.Enter Then
            Console.WriteLine("Enter")
         End If

 
    End Sub
End Class

OUTPUT OF THE APPLICATION

keyevent.jpg

Categories

More Articles

© 2019 DotNetHeaven. All rights reserved.