Loop over controls in container

Loop over controls in container

Multiple loop could make your code impossible to debug.

Last post [Loop over all control in a form ], i show you that you can’t loop over all control in your form if you have control inside a container. A container could be a GroupBox , a TabControl or a Panel. You have controls inside Statusbar and MenuStrip and again, you can’t access them easily.

So what do we do? Here, I will do something natural but surely not efficient. I will create as much loop necessary to get all my control because I have no way to get all my control in my form directly.

I was painful to do the code and honestly, I haven’t done anything extraordinary.  I simply put the name of each control in a simple string to display them. Imagine how would it be if I wanted to do something more complex with more conditions.

Imagine 1 second if you wish to exclude some control from your search. Will you do a kind of if-not condition into each type of container? And how will you do your error handling? Oh my good!!!

Take a look at this code; surely you have done something like this in your life. Check how hard is to understand this:

Public Class Form1     Private str_temp As String     ''' <summary>     ''' I think this sub will loop over all the control, but this is not the best way to do thing     ''' </summary>     ''' <param name="sender"></param>     ''' <param name="e"></param>     ''' <remarks></remarks>     Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load         'oldloop()         Dim ctrGB As GroupBox         Dim ctrGB1 As GroupBox         Dim ctrTC As TabControl         Dim ctrMI As ToolStripItem         Dim ctrMS As MenuStrip         str_temp = ""         For Each ctr As Control In Me.Controls             If TypeOf ctr Is GroupBox Then                 ctrGB = CType(ctr, GroupBox)                 For Each ctr1 As Control In ctrGB.Controls                     If TypeOf ctr1 Is GroupBox Then                         ctrGB1 = CType(ctr1, GroupBox)                         str_temp = str_temp & ctrGB1.Name & vbCrLf                     ElseIf TypeOf ctr1 Is TabControl Then                         ctrTC = CType(ctr1, TabControl)                         For Each ctrTP As TabPage In ctrTC.TabPages                             For Each ctrTP1 As Control In ctrTP.Controls                                 str_temp = str_temp & ctrTP1.Name & vbCrLf                             Next                             str_temp = str_temp & ctrTP.Name & vbCrLf                         Next                         str_temp = str_temp & ctrTC.Name & vbCrLf                     Else                         str_temp = str_temp & ctr1.Name & vbCrLf                     End If                 Next                 str_temp = str_temp & ctrGB.Name & vbCrLf             ElseIf TypeOf ctr Is TabControl Then                 ctrTC = CType(ctr, TabControl)                 For Each ctrTP As TabPage In ctrTC.TabPages                     For Each ctrTP1 As Control In ctrTP.Controls                         str_temp = str_temp & ctrTP1.Name & vbCrLf                     Next                 Next                 str_temp = str_temp & ctr.Name & vbCrLf             ElseIf TypeOf ctr Is MenuStrip Then                 ctrMS = CType(ctr, MenuStrip)                 str_temp = str_temp & ctrMS.Name & vbCrLf                 For index1 = 0 To ctrMS.Items.Count - 1 Step 1                     Dim strTS As ToolStripMenuItem                     strTS = ctrMS.Items(index1)                     str_temp = str_temp & strTS.Name & vbCrLf                     For index2 = 0 To strTS.DropDownItems.Count - 1 Step 1                         ctrMI = strTS.DropDownItems.Item(index2)                         str_temp = str_temp & ctrMI.Name & vbCrLf                     Next                 Next                     str_temp = str_temp & ctrMS.Name & vbCrLf             ElseIf TypeOf ctr Is StatusStrip Then                 ' ok, i am now too lazy to do work here, you understand                 ' all the work             Else                     str_temp = str_temp & ctr.Name & vbCrLf             End If         Next         MsgBox(str_temp)     End Sub     Private Sub oldloop() 'this loop will not reach every loop in the form         str_temp = ""         For Each ctr As Control In Me.Controls             str_temp = str_temp & ctr.Name & vbCrLf         Next         MsgBox(str_temp)     End Sub End Class

I you run the program; of course you might have the entire control name from my sample program.

I haven’t suggested anything better in this post. I will leave at is. Fell free to comment here and bring suggestions.

I don’t thing this is specially a Visual Basic problem. It happens to everyone.

It happens to me when I have to do something quickly and don’t have the time to make a clean code.

References :

My web site : Check Technologies

My Visual Basic program : Visual Studio 2010 Professional (Old Version)

Download Sample Project : SamplePrivatePublic.zip