Error: Form1 is a type of windowsApplication cannot be used as an expression - vb.net

Question

How to solve error when passing and returning some data across the form in visual basic.
Error: Form1 is a type of windowsApplication cannot be used as an
expression
showin error on "Form 1" (Public Class Form1)
FORM 1 CODE
Public Class Form1
Dim eid As String = ""
Public Sub New(ByVal empid As String)
InitializeComponent()
eid = empid
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Declare a variable of string type
Dim pass As String = TextBox1.Text
Dim frm As New Form2(pass)
frm.ShowDialog()
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Label2.Text = eid.ToString()
End Sub
End Class
FORM 2 CODE
Public Class Form2
Dim eid As String = ""
Public Sub New(ByVal empid As String)
InitializeComponent()
eid = empid
End Sub
Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Label1.Text = eid.ToString()
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim value As String = TextBox2.Text
Dim fr As New Form1(value)
fr.ShowDialog()
End Sub
End Class

Answer 1

To solve your error message add this to your Form1 Class
Public Sub New()
InitializeComponent()
End Sub
If you are trying to pass values between forms, you might find this link useful...
http://grantwinney.com/passing-data-between-two-forms-in-winforms/

Answer 2

Public Class Form1
Dim eid As String = ""
Public Sub New(ByVal empid As String)
InitializeComponent()
eid = empid
End Sub
Public Sub New()
InitializeComponent()
End Sub
startup form isn't being called with any parameters
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
'Declare a variable of string type
Dim pass As String = TextBox1.Text
Dim frm As New Form2(pass)
frm.ShowDialog()
End Sub
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Label2.Text = eid.ToString()
End Sub
End Class

Answer 3

It happens when you change the project type from class library to windows forms in visual studio.
Head to Application.Designer.vb in your project and there you'll find something like this:
Namespace My
'NOTE: This file is auto-generated; do not modify it directly. To make changes,
' or if you encounter build errors in this file, go to the Project Designer
' (go to Project Properties or double-click the My Project node in
' Solution Explorer), and make changes on the Application tab.
'
Partial Friend Class MyApplication
<Global.System.Diagnostics.DebuggerStepThroughAttribute()> _
Public Sub New()
MyBase.New(Global.Microsoft.VisualBasic.ApplicationServices.AuthenticationMode.Windows)
Me.IsSingleInstance = false
Me.EnableVisualStyles = true
Me.SaveMySettingsOnExit = true
Me.ShutDownStyle = Global.Microsoft.VisualBasic.ApplicationServices.ShutdownMode.AfterMainFormCloses
End Sub
<Global.System.Diagnostics.DebuggerStepThroughAttribute()> _
Protected Overrides Sub OnCreateMainForm()
Me.MainForm = Global.AeonLabs.Layouts.Main.mainAppLayoutForm
End Sub
End Class
End Namespace
in the sub OnCreateMainForm() where it has OnCreateMainForm change it to something like this
Protected Overrides Sub OnCreateMainForm()
Me.MainForm = New Global.AeonLabs.Layouts.Main.mainAppLayoutForm
End Sub
and you'll be good to go!!