c#-combining two forms

I want to combine two forms as in the image i have attached.I am able to do the two forms (login form and application form seperately)right now I am not able to make application form to appear in the background of the login form.this is my screen i what.there is any command specific to make the two form combine as in the screen.Please help me.Thanks 开发者_如何转开发in advance

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To display a modal dialog, from your application form you can try

using(LoginForm loginForm = new LoginForm())
{
    loginForm.StartPosition = FormStartPosition.CenterParent;
    DialogResult dialogResult = loginForm.ShowDialog(this); 

    if(dialogResult == DialogResult.OK)
    {
       ...
    }
}