KeyEventArgs クラス
KeyDown イベントまたは KeyUp イベントのデータを提供します。
この型のすべてのメンバの一覧については、KeyEventArgs メンバ を参照してください。
System.Object
System.EventArgs
System.Windows.Forms.KeyEventArgs
<ComVisible(True)>
Public Class KeyEventArgs Inherits EventArgs
[C#]
[ComVisible(true)]
public class KeyEventArgs : EventArgs
[C++]
[ComVisible(true)]
public __gc class KeyEventArgs : public EventArgs
[JScript]
public
ComVisible(true)
class KeyEventArgs extends EventArgs
スレッドセーフ
この型の public static (Visual Basicでは Shared) のすべてのメンバは、マルチスレッド操作で安全に使用できます。インスタンスのメンバの場合は、スレッドセーフであるとは限りません。
解説
各 KeyDown イベントまたは KeyUp イベントに伴い、ユーザーが押したキーおよび同時に任意の修飾子キー (Ctrl、Alt、および Shift) が押されたかどうかを指定する KeyEventArgs が渡されます。
KeyDown イベントは、ユーザーが任意のキーを押すと発生します。 KeyUp イベントは、ユーザーが押していたキーを離すと発生します。キーを押し続けている間は、キーが繰り返されるたびに KeyDown イベントが複製され、ユーザーがキーを離すと KeyUp イベントが 1 つだけ生成されます。
キーが押されている間も KeyPress イベントが発生します。各 KeyPress イベントに伴い KeyPressEventArgs が渡され、各キーを押した結果作成される文字を指定します。
イベント モデルの詳細については、「 イベントとデリゲート 」を参照してください。
使用例
' This example demonstrates how to use the KeyDown event with the Help class to display
' pop-up style help to the user of the application. The example filters for all variations
' of pressing the F1 key with a modifier key by using the KeyEventArgs properties passed
' to the event handling method.
' When the user presses any variation of F1 that includes any keyboard modifier, the Help
' class displays a pop-up window, similar to a ToolTip, near the control. If the user presses
' ALT + F2, a different Help pop-up is displayed with additional information. This example assumes
' that a TextBox control, named textBox1, has been added to the form and its KeyDown
' event has been contected to this event handling method.
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 'textBox1_KeyDown
[C#]
// This example demonstrates how to use the KeyDown event with the Help class to display
// pop-up style help to the user of the application. The example filters for all variations
// of pressing the F1 key with a modifier key by using the KeyEventArgs properties passed
// to the event handling method.
// When the user presses any variation of F1 that includes any keyboard modifier, the Help
// class displays a pop-up window, similar to a ToolTip, near the control. If the user presses
// ALT + F2, a different Help pop-up is displayed with additional information. This example assumes
// that a tTextBox control, named textBox1, has been added to the form and its KeyDown
// event has been contected to this event handling method.
private void textBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
// Determine whether the key entered is the F1 key. If it is, display Help.
if(e.KeyCode == Keys.F1 && (e.Alt || e.Control || e.Shift))
{
// Display a pop-up Help topic to assist the user.
Help.ShowPopup(textBox1, "Enter your name.", new Point(textBox1.Bottom, textBox1.Right));
}
else if(e.KeyCode == Keys.F2 && e.Modifiers == Keys.Alt)
{
// 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, this.textBox1.Left));
}
}
[C++]
// This example demonstrates how to use the KeyDown event with the Help class to display
// pop-up style help to the user of the application. The example filters for all variations
// of pressing the F1 key with a modifier key by using the KeyEventArgs properties passed
// to the event handling method.
// When the user presses any variation of F1 that includes any keyboard modifier, the Help
// class displays a pop-up window, similar to a ToolTip, near the control. If the user presses
// ALT + F2, a different Help pop-up is displayed with additional information. This example assumes
// that a tTextBox control, named textBox1, has been added to the form and its KeyDown
// event has been contected to this event handling method.
private:
void textBox1_KeyDown(Object* /*sender*/, System::Windows::Forms::KeyEventArgs* e)
{
// Determine whether the key entered is the F1 key. If it is, display Help.
if(e->KeyCode == Keys::F1 && (e->Alt || e->Control || e->Shift))
{
// Display a pop-up Help topic to assist the user.
Help::ShowPopup(textBox1, S"Enter your name.", Point(textBox1->Bottom, textBox1->Right));
}
else if(e->KeyCode == Keys::F2 && e->Modifiers == Keys::Alt)
{
// Display a pop-up Help topic to provide additional assistance to the user.
Help::ShowPopup(textBox1, S"Enter your first name followed by your last name. Middle name is optional.",
Point(textBox1->Top, this->textBox1->Left));
}
}
[Visual Basic]
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 mose cursor, begin editing.
Dim editNode As TreeNode = treeView1.GetNodeAt( _
treeView1.PointToClient(Control.MousePosition))
If Not (editNode Is 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
[C#]
private void treeView1_KeyDown(object sender, KeyEventArgs e)
{
/* If the 'Alt' and 'E' keys are pressed,
* allow the user to edit the TreeNode label. */
if(e.Alt && e.KeyCode == Keys.E)
{
treeView1.LabelEdit = true;
// If there is a TreeNode under the mose cursor, begin editing.
TreeNode editNode = treeView1.GetNodeAt(
treeView1.PointToClient(Control.MousePosition));
if(editNode != null)
{
editNode.BeginEdit();
}
}
}
private void treeView1_AfterLabelEdit(object sender, NodeLabelEditEventArgs e)
{
// Disable the ability to edit the TreeNode labels.
treeView1.LabelEdit = false;
}
[C++]
private:
void treeView1_KeyDown(Object* /*sender*/, KeyEventArgs* e) {
/* If the 'Alt' and 'E' keys are pressed,
* allow the user to edit the TreeNode label. */
if (e->Alt && e->KeyCode == Keys::E) {
treeView1->LabelEdit = true;
// If there is a TreeNode under the mose cursor, begin editing.
TreeNode* editNode = treeView1->GetNodeAt(
treeView1->PointToClient(Control::MousePosition));
if (editNode != 0) {
editNode->BeginEdit();
}
}
}
void treeView1_AfterLabelEdit(Object* /*sender*/, NodeLabelEditEventArgs* /*e*/) {
// Disable the ability to edit the TreeNode labels.
treeView1->LabelEdit = false;
}
[Visual Basic]
' 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
End Sub 'textBox1_KeyDown
' 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 'textBox1_KeyPress
End Class 'Form1
[C#]
// Boolean flag used to determine when a character other than a number is entered.
private bool nonNumberEntered = false;
// Handle the KeyDown event to determine the type of character entered into the control.
private void textBox1_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
// 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 || e.KeyCode > Keys.D9)
{
// Determine whether the keystroke is a number from the keypad.
if (e.KeyCode < Keys.NumPad0 || e.KeyCode > Keys.NumPad9)
{
// Determine whether the keystroke is a backspace.
if(e.KeyCode != Keys.Back)
{
// A non-numerical keystroke was pressed.
// Set the flag to true and evaluate in KeyPress event.
nonNumberEntered = true;
}
}
}
}
// This event occurs after the KeyDown event and can be used to prevent
// characters from entering the control.
private void textBox1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
// Check for the flag being set in the KeyDown event.
if (nonNumberEntered == true)
{
// Stop the character from being entered into the control since it is non-numerical.
e.Handled = true;
}
}
[C++]
// Boolean flag used to determine when a character other than a number is entered.
private:
bool nonNumberEntered;
// Handle the KeyDown event to determine the type of character entered into the control.
void textBox1_KeyDown(Object* /*sender*/, System::Windows::Forms::KeyEventArgs* e)
{
// 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 || e->KeyCode > Keys::D9)
{
// Determine whether the keystroke is a number from the keypad.
if (e->KeyCode < Keys::NumPad0 || e->KeyCode > Keys::NumPad9)
{
// Determine whether the keystroke is a backspace.
if(e->KeyCode != Keys::Back)
{
// A non-numerical keystroke was pressed.
// Set the flag to true and evaluate in KeyPress event.
nonNumberEntered = true;
}
}
}
}
// This event occurs after the KeyDown event and can be used to prevent
// characters from entering the control.
void textBox1_KeyPress(Object* /*sender*/, System::Windows::Forms::KeyPressEventArgs* e)
{
// Check for the flag being set in the KeyDown event.
if (nonNumberEntered == true)
{
// Stop the character from being entered into the control since it is non-numerical.
e->Handled = true;
}
}
[JScript] JScript のサンプルはありません。Visual Basic、C#、および C++ のサンプルを表示するには、このページの左上隅にある言語のフィルタ ボタン .gif)
をクリックします。
必要条件
名前空間: System.Windows.Forms
プラットフォーム: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 ファミリ, .NET Compact Framework - Windows CE .NET
アセンブリ: System.Windows.Forms (System.Windows.Forms.dll 内)
参照
KeyEventArgs メンバ | System.Windows.Forms 名前空間 | OnKeyDown | KeyDown | OnKeyUp | KeyUp | KeyPressEventArgs | OnKeyPress | KeyPress