private void 修改密码PToolStripMenuItem_Click(object sender, EventArgs e)
{

        Form4 Form4 = new Form4();
        Form4.MdiParent = this;
        Form4.StartPosition = FormStartPosition.CenterScreen;
        Form4.Show();
    }

private void 修改密码PToolStripMenuItem_Click(object sender, EventArgs e)
{

        Form4 Form4 = new Form4();
        Form4.MdiParent = this;
        Form4.StartPosition = FormStartPosition.CenterScreen;
        Form4.Show();
    }