Form.ActiveForm 属性
重要
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获取此应用程序的当前活动窗体。
public:
static property System::Windows::Forms::Form ^ ActiveForm { System::Windows::Forms::Form ^ get(); };C#
public static System.Windows.Forms.Form ActiveForm { get; }C#
public static System.Windows.Forms.Form? ActiveForm { get; }member this.ActiveForm : System.Windows.Forms.FormPublic Shared ReadOnly Property ActiveForm As FormForm，表示当前活动窗体，或者如果没有活动窗体，则为 null。
以下示例获取活动窗体并禁用窗体上的所有控件。 该示例使用 Controls 窗体的集合循环访问窗体上的每个控件并禁用控件。
void DisableActiveFormControls()
{
// Create an instance of a form and assign it the currently active form.
Form^ currentForm = Form::ActiveForm;
// Loop through all the controls on the active form.
for ( int i = 0; i < currentForm->Controls->Count; i++ )
{
// Disable each control in the active form's control collection.
currentForm->Controls[ i ]->Enabled = false;
}
}
C#
public void DisableActiveFormControls()
{
// Create an instance of a form and assign it the currently active form.
Form currentForm = Form.ActiveForm;
// Loop through all the controls on the active form.
for (int i = 0; i < currentForm.Controls.Count; i++)
{
// Disable each control in the active form's control collection.
currentForm.Controls[i].Enabled = false;
}
}
Public Sub DisableActiveFormControls()
' Create an instance of a form and assign it the currently active form.
Dim currentForm As Form = Form.ActiveForm
' Loop through all the controls on the active form.
Dim i As Integer
For i = 0 To currentForm.Controls.Count - 1
' Disable each control in the active form's control collection.
currentForm.Controls(i).Enabled = False
Next i
End Sub
可以使用此方法获取对当前活动窗体的引用，以对窗体或其控件执行操作。
如果应用程序是多文档接口 (MDI) 应用程序，请使用 ActiveMdiChild 该属性获取当前活动的 MDI 子窗体。
| 产品 | 版本 |
|---|---|
| .NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 |
| Windows Desktop | 3.0, 3.1, 5, 6, 7 |