class连接数据库

Posted 2020-11-07 公子兔

import pymysql
class MyDb(object):
    def __init__(self,host,user,passwd,db,port=3306,charset=‘utf8‘):
        try:
            self.coon=pymysql.connect(
                host=host,user=user,passwd=passwd,port=port,charset=charset,db=db,
                autocommit=True,#自动提交
            )
        except Exception as e:
            print(‘数据库连接失败！%s‘%e)
        else:
            self.cur=self.coon.cursor(cursor=pymysql.cursors.DictCursor)#返回字典型
    def ex_sql(self,sql):
        try:
         self.cur.execute(sql)
        except Exception as e:
            print("SQL语句错误！%s"%sql)
        else:
            self.res=self.cur.fetchall()
            return self.res
    def __del__(self):#析构函数，实例被销毁时执行
        self.cur.close()
        self.coon.close()
        print(‘over..........‘)
my=MyDb(‘118.24.3.40‘,‘jxz‘,‘123456‘,‘jxz‘)#my被销毁的时候执行析构函数
my.ex_sql(‘select * from stu‘)
print(my.res)
print(‘最后一行‘)