C# Winform load method

Question

I'm writing WinForm app where every new form is child form of main form. Every time I call menustripitem click I use such code:

bool opened = false;
foreach (Form forma in Application.OpenForms)
{
    if (forma is frm_formname)
    {
        opened = true;
        break;
    }
}

if (!opened)
{
    frm_formname frm = new frm_formname();
    frm.MdiParent = this;
    frm.Show();
}
else
{
    MessageBox.Show("Form already exist");
}

How can I change the code to make a method from this code where I will pass formname and mainformname as parameter and on click event call this method sending this 2 parameters not the whole code?

Answer 1

You can't use a string, you should pass the type of the form you're looking for as a parameter. Something like this should work (untested!).

public void FindOrCreateForm(Type formType)
{
bool opened = false;
foreach (Form forma in Application.OpenForms)
{
    if (forma.GetType() == formType)
    {
        opened = true;
        break;
    }
}
if (!opened)
{
    Form frm = (Form) Activator.CreateInstance(formType);
    frm.MdiParent = this;
    frm.Show();
}
else
{
    MessageBox.Show("Form already exist");
}
}