Textbox update from other form

[ident]

Your form that updates the textbox should look a little some thing like

TextBox is private not friend.

Public Class MainForm
 
    Public WriteOnly Property UpdateDisplayValue As String
        Set(ByVal value As String)
            If value.Trim <> String.Empty Then
                Me.PrivateTextBox.Text = value
            End If
        End Set
    End Property
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim frm As New UpdateForm(Me)
        frm.ShowDialog()
    End Sub
 
End Class

The form that updates the textbox looks a little some thing like

Public Class UpdateForm
 
    Private m_mainForm As MainForm
 
    Public Sub New(ByVal MainForm As MainForm)
        InitializeComponent()
        Me.m_mainForm = MainForm
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Me.Close()
    End Sub
 
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Me.m_mainForm.UpdateDisplayValue = "Some value"
    End Sub
End Class

All exe removed

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