本文整理汇总了VB.NET中System.Windows.Forms.KeyEventArgs.KeyCode属性的典型用法代码示例。如果您正苦于以下问题:VB.NET KeyEventArgs.KeyCode属性的具体用法?VB.NET KeyEventArgs.KeyCode怎么用?VB.NET KeyEventArgs.KeyCode使用的例子?那么, 这里精选的属性代码示例或许可以为您提供帮助。您也可以进一步了解该属性所在类System.Windows.Forms.KeyEventArgs
的用法示例。
在下文中一共展示了KeyEventArgs.KeyCode属性的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的VB.NET代码示例。
示例1: AndAlso
Private Sub textBox1_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles textBox1.KeyDown
' Determine whether the key entered is the F1 key. If it is, display Help.
If e.KeyCode = Keys.F1 AndAlso (e.Alt OrElse e.Control OrElse e.Shift) Then
' Display a pop-up Help topic to assist the user.
Help.ShowPopup(textBox1, "Enter your name.", New Point(textBox1.Bottom, textBox1.Right))
ElseIf e.KeyCode = Keys.F2 AndAlso e.Modifiers = Keys.Alt Then
' Display a pop-up Help topic to provide additional assistance to the user.
Help.ShowPopup(textBox1, "Enter your first name followed by your last name. Middle name is optional.", _
New Point(textBox1.Top, Me.textBox1.Left))
End If
End Sub
示例2: If
Private Sub treeView1_KeyDown(sender As Object, _
e As KeyEventArgs) Handles treeView1.KeyDown
' If the 'Alt' and 'E' keys are pressed,
' allow the user to edit the TreeNode label.
If e.Alt And e.KeyCode = Keys.E Then
treeView1.LabelEdit = True
' If there is a TreeNode under the mouse cursor, begin editing.
Dim editNode As TreeNode = treeView1.GetNodeAt( _
treeView1.PointToClient(System.Windows.Forms.Control.MousePosition))
If (editNode IsNot Nothing) Then
editNode.BeginEdit()
End If
End If
End Sub
Private Sub treeView1_AfterLabelEdit(sender As Object, _
e As NodeLabelEditEventArgs) Handles treeView1.AfterLabelEdit
' Disable the ability to edit the TreeNode labels.
treeView1.LabelEdit = False
End Sub
示例3:
' Boolean flag used to determine when a character other than a number is entered.
Private nonNumberEntered As Boolean = False
' Handle the KeyDown event to determine the type of character entered into the control.
Private Sub textBox1_KeyDown(sender As Object, e As System.Windows.Forms.KeyEventArgs) _
Handles textBox1.KeyDown
' Initialize the flag to false.
nonNumberEntered = False
' Determine whether the keystroke is a number from the top of the keyboard.
If e.KeyCode < Keys.D0 OrElse e.KeyCode > Keys.D9 Then
' Determine whether the keystroke is a number from the keypad.
If e.KeyCode < Keys.NumPad0 OrElse e.KeyCode > Keys.NumPad9 Then
' Determine whether the keystroke is a backspace.
If e.KeyCode <> Keys.Back Then
' A non-numerical keystroke was pressed.
' Set the flag to true and evaluate in KeyPress event.
nonNumberEntered = True
End If
End If
End If
'If shift key was pressed, it's not a number.
If Control.ModifierKeys = Keys.Shift Then
nonNumberEntered = true
End If
End Sub
' This event occurs after the KeyDown event and can be used
' to prevent characters from entering the control.
Private Sub textBox1_KeyPress(sender As Object, e As System.Windows.Forms.KeyPressEventArgs) _
Handles textBox1.KeyPress
' Check for the flag being set in the KeyDown event.
If nonNumberEntered = True Then
' Stop the character from being entered into the control since it is non-numerical.
e.Handled = True
End If
End Sub