private void frmAdmin_Clear() { txtFullname.Text = null; txtUsername.Text = null; txtPassword.Text = null; txtConfirmPassword.Text = null; txtUsername.Enabled = true; btnThem.Enabled = false; btnSua.Enabled = false; btnXoa.Enabled = false; btnExit.Enabled = true; dgvUsers.Enabled = true; dtUsers = new DataTable(); dtPermissions = new DataTable(); bllUsers = new UsersBLL(); bllPermission = new PermissionBLL(); dtUsers = bllUsers.selectUserDetails(); dtPermissions = bllPermission.getPermission(); dgvUsers.AutoGenerateColumns = false; dgvUsers.DataSource = dtUsers; cboPermission.DataSource = dtPermissions; cboPermission.DisplayMember = "Permission"; cboPermission.ValueMember = "IdPermission"; }