Open Form only one Time

ilhami caliskan

Hello All,

I open several Forms in one main Form...
But my problem is that an allready opened Form is opening the second... third... fourth... time if I click on that button.
How it is possible to void a new opening of a allready opened Form?
and If possible how can I sent a warning, that the Form is allready open...?

thank you in advance

my procedure to open a form

SimFrm gsm = new SimFrm(this);
gsm.TopLevel = False;
this.Controls.Add(gsm);
gsm.Show();

3 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes14y ago
Accepted answer
Try this:

if(Application.OpenForms["gsm"] == null)
{
SimFrm gsm = new SimFrm(this);
gsm.Name = "gsm";
gsm.TopLevel = False;
this.Controls.Add(gsm);
gsm.Show();
}
else
{
MessageBox.Show("gsm form is already open");
}
Vulpes14y ago
In that case I'd do:

private void btnRoundUp_Click(object sender, EventArgs e)
{
if(Application.OpenForms["frmRoundUp"] == null)
{
frmRoundUp frm = new frmRoundUp();
frm.Name = "frmRoundUp";
frm.Show();
}
else
{
MessageBox.Show("RoundUp form is already open");
}
}
raj kiran14y ago
Hi,

Even i have the same problem but i am not having any idea about except to open a form this way and i am doing by

private void btnRoundUp_Click(object sender, EventArgs e)
        {

            frmRoundUp frm = new frmRoundUp();
            frm.Show();
        }

What should i do here to stop the other form opening for number of this if opened one this display it again on top of all forms

Thanks you for looking to my quire