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POIssue while invoking a form from another using System.Window.Forms.Invoke(delegate)
 

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    <p>I have two forms and 1 singleton class. I am initalizing the singleton class in btn_A_Click of formA.</p> <pre><code>public partial class frmA : Form { public frmA() { InitializeComponent(); frmB frmB; } private void btn_A_Click(object sender, EventArgs e) { SessionMgmt.GetInstance().StartFormB(); } } </code></pre> <p>This is my singleton class and here I am trying to use Forms.Invoke() method. </p> <pre><code>public class SessionMgmt { static SessionMgmt _sessinMgr; frmB frB; private SessionMgmt() { frB = new frmB(); } public static SessionMgmt GetInstance() { if (_sessinMgr != null) return _sessinMgr; else { _sessinMgr = new SessionMgmt(); return _sessinMgr; } } public bool StartFormB() { frB.Invoke(new EventHandler(DisplayFrmB)); return true; } private void DisplayFrmB(Object o, EventArgs e) { frB.Visible = true; frB.Refresh(); } </code></pre> <p>}</p> <p>This is my formB.</p> <pre><code>public partial class frmB : Form { } </code></pre> <p>But from the <code>frB.Invoke(new EventHandler(DisplayFrmB));</code> method it throws the following exception:</p> <blockquote> <p>Invoke or BeginInvoke cannot be called on a control until the window handle has been created.</p> </blockquote> <p>I can't figure out the issue, please help or advice me if I miss anything.</p> <p><strong>EDIT</strong></p> <p>The following structure is the way my current project is displaying the next form. It was done by VB.NET and I need to use similar kind of thing in the new project which uses C#. I saw the Invoke function which points to an event and then to a function. In that function it just makes the Form.Visible=true and Form.Refresh. But for understanding I just tried a POc and followed the same steps ,but it is not yet solved.</p>
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    1. COCan you post the bare minimum vb.net code you are trying to replicate?
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