Question

我是Visual Basic.NET的新手，我需要写一段代码来找到Windows窗体中（用户控件/控件）的最顶级父级。

我在Windows窗体上有数百个控件，有些是用户控件和一些内置的Windows控件

我测试的代码是添加多个IF条件，但是当控件嵌套多于2个级别时，很难添加IF条件。

像：的表 - 面板 - - 面板 ------分组框中 --------文本框

'Here is simple code
'A TextBox inside Panel control
Dim parent_control As Control = TryCast(txtbox, Control) 'casting that Control in generic Control
if parent_control.Parent Is Nothing Then
   Return 
Else
   Return parent_control.Parent.Parent
End If

如果有人在这方面指导我，我将非常感激。

Answer 1

这是通过递归完成的：

#Region "Get Ultimate Parent"
Private Function GetParentForm(ByVal parent As Control) As Control
    Dim parent_control As Control = TryCast(parent, Control)
    '------------------------------------------------------------------------
    'Specific to a control means if you want to find only for certain control
    If TypeOf parent_control Is myControl Then   'myControl is of UserControl
        Return parent_control
    End If
    '------------------------------------------------------------------------
    If parent_control.Parent Is Nothing Then
        Return parent_control
    End If
    If parent IsNot Nothing Then
        Return GetParentForm(parent.Parent)
    End If
    Return Nothing
End Function
#End Region

它非常适合我。

Answer 2

这里不需要递归。

Private Function UltimateParent(ByVal control as Control) As Control

  Do
    If Nothing Is control.Parent
      Return control
    Else
      control = control.Parent
    End If
  Loop

End Function

Answer 3

* *您可以使用

Dim Form As System.Windows.Forms.Form
Form = Combobox.FindForm()

＆＃39;直接找到任何控制的父母形式，直到* *

Answer 4

最终将是形式，但你真的在寻找一种方法来追踪，你可以使用递归或循环：

Public Function FindTopMostParent(ctrl As Control) As Control
    If ctrl.Parent Is Nothing Then
        Return ctrl '// or nothing?
    End If

    Return FindTopMostParent(ctrl.Parent)
End Function

Public Function FindTopMostParent_v2(ctrl As Control) As Control
    Dim output As Control = ctrl

    While output.Parent IsNot Nothing
        output = output.Parent
    End While

    Return output
End Function

Answer 5

最简单

Public Function GetUltimateParent(ByVal ofThisControl As Control) As Control
    If ofThisControl Is Nothing return Nothing 'Error Check

    Dim ultimateParent As Control = ofThisControl
    While Not ultimateParent.Parent Is Nothing
        ultimateParent = ultimateParent.Parent
    End While

    Return ultimateParent
 End Function

在Vb.Net中寻找控件的最终父级

5 个答案: