CODEWITHSUNDEEP
.netvb.netobjectreferencecontrols
user1704812
user1704812

Reputation:

How to reference an existing object in VB.net?

How do you reference an existing object in vb.net?

To describe my problem more specifically, I have my main form Form1 that loads when I start the application. Form1 has a datagridview dgv1. I have another form form2 in the project with a bunch of textboxes. On clicking a button on Form1 I create an instance of form2. From form2 how do I reference the existing form1 to populate dgv1 with input from the texboxes on form2?

Upvotes: 2

Views: 1429

Answers (2)

Matt Wilko
Matt Wilko

Reputation: 27342

Easy fix: You can access a control on Form1 directly from Form2

So if you have DataGridView1 on Form1, in the Form2 code you can access it by using Form1.DataGridView1

Note: this is not a good design, because you are tightly coupling your two forms, you would be better to pass a reference to a DataGridView into Form2 rather than updating it directly

in the Constructor of Form2 force it to pass your reference:

Public Class Form2
    Private _dgv As DataGridView
    Public Sub New(dgv As DataGridView)

        ' This call is required by the designer.
        InitializeComponent()

        ' Add any initialization after the InitializeComponent() call.

        'ensure we have a value object
        If dgv Is Nothing Then Throw New ArgumentNullException("DataGridView")
        _dgv = dgv
    End Sub

    Private Sub frmRibbonTest_Resize(sender As Object, e As EventArgs) Handles Me.Resize
        Dim rect = RibbonControl1.ClientRectangle
        DataGridView1.Location = New Point(rect.X, rect.Y)
        DataGridView1.Height = rect.Height
        DataGridView1.Width = rect.Width
    End Sub
End Class

Then when you create form2 from form1, use your reference like this:

 Dim f2 = New Form2(Me.DataGridView1)
 f2.Show()

Upvotes: 1

Dai
Dai

Reputation: 155708

You need to pass a reference-to-Form1 to Form2. Use the Me keyword to get a reference to the object currently executing:

In Form1.vb:

Sub Form1_OpenForm2()

    Dim form2 As New Form2()
    form2.AcceptForm1( Me )
    form2.Show()
End Sub

In Form2.vb:

Private _form1 As Form1

Public Sub AcceptForm1(form1 As Form1)
    _form1 = form1
End Sub

Upvotes: 1

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