private void btnOk_Click(object sender, EventArgs e) { if (context.Users.Any(u => u.UserName == cmbUsername.Text) && context.Roles.Any(r => r.Name == cmbRole.Text)) { if (userIdentity.IsInRole(UserIdentity.SessionUser, "Admin")) { if (userIdentity.ChangeRole(cmbUsername.Text, cmbRole.Text)) { XtraMessageBox.Show("Change user Role successfully", "OK"); this.DialogResult = DialogResult.OK; context.Dispose(); userIdentity.Dispose(); this.Close(); } ; } else { XtraMessageBox.Show("You do not have permission to perform this action"); btnCancel_Click(this, null); } } else { XtraMessageBox.Show("Username or Role not found", "Error"); return; } }