权限界面程序

public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }

        private void btnLogin_Click(object sender, EventArgs e)
        {
            //通过获取设置的DialogResult结果来确定点击的按钮
            this.DialogResult = DialogResult.OK;
        }

        private void btnCancel_Click(object sender, EventArgs e)
        {
            this.DialogResult = DialogResult.Cancel;
        }
    }

主程序界面

        private void button1_Click(object sender, EventArgs e)
        {
            Form2 f = new Form2();
            f.ShowDialog();
            if (f.DialogResult ==DialogResult .OK )
            {
                MessageBox.Show("确认");
            }
            else if (f.DialogResult ==DialogResult .Cancel )
            {
                MessageBox.Show("取消");

            }
            else
            {
                MessageBox.Show("其他");
            }
        }