Question

如何找出Windows Forms中关注哪个控件？

Answer 1

Form.ActiveControl可能就是您想要的。

Answer 2

请注意，使用层次结构时，单次调用ActiveControl是不够的。想象：

Form
    TableLayoutPanel
        FlowLayoutPanel
            TextBox (focused)

(formInstance).ActiveControl将返回对TableLayoutPanel的引用，而不是TextBox

所以使用这个（完全披露：改编自this C# answer）

  Function FindFocussedControl(ByVal ctr As Control) As Control
    Dim container As ContainerControl = TryCast(ctr, ContainerControl)
    Do While (container IsNot Nothing)
      ctr = container.ActiveControl
      container = TryCast(ctr, ContainerControl)
    Loop
    Return ctr
  End Function

Answer 3

在C＃中我这样做：

        if (txtModelPN != this.ActiveControl)
            txtModelPN.BackColor = Color.White;

txtModelPN是一个文本框，我在输入时突出显示，鼠标输入和取消突出显示在Leave，MouseLeave上。除非它是当前控件，否则我不将背景设置为白色。

VB等价物就像这样

IF txtModelPN <> Me.ActiveControl Then
   txtModelPN.BackColor = Color.White
End If

Answer 4

您可以使用表单的ActiveControl属性，并可以使用该控件。

me.ActiveControl

或者

Form.ActiveControl

Answer 5

您可以使用它来按控制名称查找。

    If DataGridView1.Name = Me.ActiveControl.Name Then
        TextBox1.Visible = True
    Else
        TextBox1.Visible = False
    End If

Answer 6

我使用了以下内容：

Private bFocus = False
Private Sub txtUrl_MouseEnter(sender As Object, e As EventArgs) Handles txtUrl.MouseEnter
    If Me.ActiveControl.Name <> txtUrl.Name Then
        bFocus = True
    End If
End Sub

Private Sub txtUrl_MouseUp(sender As Object, e As MouseEventArgs) Handles txtUrl.MouseUp
    If bFocus Then
        bFocus = False
        txtUrl.SelectAll()
    End If
End Sub

我仅在MouseEnter上设置变量以改善魔术效果

Answer 7

这些方面的东西：

Protected Function GetFocusControl() As Control
    Dim focusControl As Control = Nothing

    ' Use this to get the Focused Control: 
    Dim focusHandle As IntPtr = GetFocus()
    If IntPtr.Zero.Equals(focusHandle) Then          
      focusControl = Control.FromHandle(focusHandle)
    End If

    ' Note that it returns NOTHING if there is not a .NET control with focus 
    Return focusControl
End Function

我认为这段代码来自windowsclient.net，但已经有一段时间了......

如何找出.NET Windows Forms中哪些控件具有焦点？

7 个答案: