def alter_managerself # 获取选中的行号 selected_row = selftable_managercurrentRow if selected_row 0 QMessageBoxwarningself 警告 请先选择要修改的读者！ return # 获取选中行的借书证

def alter_manager(self): # 获取选中的行号 selected_row = self.table_manager.currentRow() if selected_row < 0: QMessageBox.warning(self, '警告', '请先选择要修改的读者！') return # 获取选中行的借书证号 manager_id = self.table_manager.item(selected_row, 0).text() # 获取用户输入的信息 new_password = self.table_manager.item(selected_row, 1).text() beizhu = self.table_manager.item(selected_row, 2).text() old_password, okPressed = QInputDialog.getText(self, "请输入旧密码", "旧密码:", QLineEdit.Password) if not okPressed: QMessageBox.warning(self, "提示", "请输入旧密码！") return

    # 连接数据库
    conn = pymysql.connect(host='localhost', user='root', password='123456', db='library', charset='utf8')
    cursor = conn.cursor()

    try:
        # 查询用户输入的用户名和旧密码是否匹配
        sql = "SELECT * FROM lad WHERE 帐号='{}' AND 密码='{}'".format(manager_id, old_password)
        cursor.execute(sql)
        result = cursor.fetchone()
        if result:
            # 如果用户名和旧密码匹配，则更新密码和备注
            sql = "UPDATE lad SET 密码='{}', 备注='{}' WHERE 帐号='{}'".format(new_password, beizhu, manager_id)
            cursor.execute(sql)
            conn.commit()
            QMessageBox.information(self, "提示", "更新成功！")
        else:
            # 如果用户名和旧密码不匹配，则提示用户
            QMessageBox.warning(self, "提示", "旧密码输入不正确！")
    except Exception as e:
        # 如果出现异常，则回滚操作并提示用户
        conn.rollback()
        QMessageBox.warning(self, "提示", "更新失败：" + str(e))
    finally:
        # 关闭数据库连接
        conn.close(