Vb.net – In vb.net, how to force validating controls within a (winform) datarepeater after the data is populated

vb.netwinforms

I have a form with a datarepeater that contains various controls (i.e. datetimepickers, text boxes, combo box) that are populated via a binding source. I also have other controls on the form that are not part of the data repeater.

I would like to force validating all controls after the data is populated. I have successfully forced validating the non-datarepeater controls using Me.ValidateChildren() at the end of my load event. However, it does not fire the validating events for the controls within the data repeater.

I have unsuccessfully tried many different attempts to set and move focus within the datarepeater controls trying to get the validating events kicked off. I am not sure where would be the best place (e.g. in drawItem? in ItemCloned?) to place the code and what it should be exactly. Here was my latest attempt:

Private Sub DataRepeater1_DrawItem(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.PowerPacks.DataRepeaterItemEventArgs) _
        Handles DataRepeater1.DrawItem

        For i = 0 To e.DataRepeaterItem.Controls.Count - 1
            e.DataRepeaterItem.Controls.Item(i).Focus()
            e.DataRepeaterItem.Controls.Item(0).Focus()
        Next

Note: I successfully handled the validating events in the data repeater caused by user input errors. However, I have the unusual situation that the data coming into my form is already bad for some of the controls. The purpose of the form is to validate the data coming in to it and from user-input.

Thanks in advance for any help. I am newbie with vb.net.

Best Answer

Have you tried calling

DataRepeater1.ValidateChildren()

after calling form's Me.ValidateChildren()

MSDN link

EDIT:

Can you try this

Private Shared Function ValidateAllChildern(cc As ContainerControl) As Boolean
    Return cc.ValidateChildren() And cc.Controls.OfType(Of ContainerControl)().[Select](Function(c) ValidateAllChildern(c)).Aggregate(True, Function(x, y) x And y)
End Function

and call

ValidateAllChildren(Me)

Related Solutions

R – How to discriminate between data binding and user actions on WinForm controls

I would suggest not handling the logic in the form code, but rather in the data class. All you need in the form is a couple of lines to set up the data binding. The data class can then take care of the rest:

Form

Private _dc As DataClass

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    _dc = New DataClass
    txtPrice.DataBindings.Add("text", _dc, "Price")
    chkOverride.DataBindings.Add("checked", _dc, "override")
End Sub

Data Class

Private _originalPrice As Double = 50

Private _price As Double = _originalPrice
Public Property Price() As Double
    Get
        Return _price
    End Get
    Set(ByVal value As Double)
        If (_price <> value) Then
            _price = value
            Override = _price <> _originalPrice
        End If
    End Set
End Property


Private _override As Boolean
Public Property Override() As Boolean
    Get
        Return _override
    End Get
    Set(ByVal value As Boolean)
        If _override <> value Then
            _override = value
            If Not _override Then Price = OriginalPrice
        End If
    End Set
End Property

No need to handle any CheckedChanged or TextChanged events in the form.

C# – Validating Data In A WinForm

Please select the form > Set the property CausesValidation to true

Select OK button and again set property CausesValidation to true

and then it will take care of all the validations.

Important points: 1) You must mention e.Cancel=true in all the validating eventhandlers

2) If your buttons are in panels then you must set panels (or any parent control's) CausesValidation property to true

Edit:

3) Validate fires just before loss of focus. While pressing Enter will cause the default button to Click, it doesn't move the focus to that button, hence no validation event will be fired if you have set forms AcceptButton Property to OK button

Best Answer

Related Solutions

R – How to discriminate between data binding and user actions on WinForm controls

C# – Validating Data In A WinForm

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