private void button1_Click(object sender, EventArgs e)
{
    List<string> names = new List<string>();
    foreach (var type in this.GetType().Assembly.GetTypes())
    {
        if (typeof(Form).IsAssignableFrom(type))
        {
            try
            {
                using (Form form = Activator.CreateInstance(type) as Form)
                {
                    names.Add(form.Text); //names.Add(form.name)
                }
            }
            catch
            {
                Console.WriteLine(string.Format("类型为 {0} 的窗体没有无参的构造函数，无法获取其名称", type));
            }
        }
    }
}