How to communicate between 2 different visual basic applications.
Simple technique by using SendMessage()
'Main app that tries to communicate with other Public Class Form1 'Project App1 Private Const APP2_MSG1 As Integer = 6541 Declare Auto Function SendMessage Lib "user32.dll" _ (ByVal hWnd As IntPtr, ByVal Msg As Integer, _ ByVal wParam As Integer, ByVal lParam As Integer) As Integer Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _ Handles Button1.Click Dim p() As Process = Process.GetProcessesByName("App2") If p.Count > 0 Then Dim hWnd As IntPtr = p(0).MainWindowHandle SendMessage(hWnd, APP2_MSG1, 0, 0) Debug.WriteLine("Msg sent") End If End Sub End Class
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