python-异常处理&操作数据库&网络编程

处理异常

money = 1000
num = input('Please enter a num:')
try:
    num = float(num)
    res = money/num

except Exception as e:#能获取到所有的异常
# except ValueError as e:#单个异常，出现异常了，就走except下面的代码
#     # print(e)
    print('你出现异常了')
    print('你输入的价格不合法。。')
# except ZeroDivisionError as e:#单个异常
#     print('除数不能为0')
else:#没有出现异常
    money-=num
    print('你的余额是%s'%money)
finally:#无论是否有异常都会执行
    print('dddddd')

 封装操作redis

import redis

class MyRedis:
    def __init__(self,host,password,port=6378,db=0):
        self.r = redis.Redis(host=host,password=password,port=port,db=db)

    def op_str(self,k,v=None,ex=-1):
        if v:
            self.r.set(k,v,ex)#set
        else:
            res = self.r.get(k)
            if res:
                return res.decode()

    def op_hash(self,name,k=None):
        if k:#判断取单个值
           res = self.r.hget(name,k)
           if res:
               return res.decode()
        else:#取所有的值
            res = {}
            for k,v in self.r.hgetall(name).items():
                res[k.decode()]=v.decode()
            return res

封装操作mysql

import pymysql

class MyDb:
    def __init__(self,host,password,user,db,port=3306,charset='utf8',autocommit=True):
        try:
            self.coon = pymysql.connect(host=host,password=password,
                                    user=user,db=db,port=port,
                                    charset=charset,autocommit=autocommit)
        except Exception as e:
            print('数据库连接失败！错误信息是%s'%e)
            raise Exception('数据库连接失败！错误信息是%s'%e)
        else:
            self.cur = self.coon.cursor(pymysql.cursors.DictCursor)

    def select_all(self,sql):
        try:
            self.cur.execute(sql)
        except Exception as e:
           res = 'sql语句错误，%s
，错误的sql是【%s】'%(e,sql)
           print(res)
        else:
            res = self.cur.fetchall()
        return res
    def select_one(self,sql):
        try:
            self.cur.execute(sql)
        except Exception as e:
           res = 'sql语句错误，%s
，错误的sql是【%s】'%(e,sql)
           print(res)
           return res
        else:
            res = self.cur.fetchone()
        return res


def other_sql(self, sql):
    try:
        self.cur.execute(sql)
    except Exception as e:
        res = 'sql语句错误，%s
，错误的sql是【%s】' % (e, sql)
        print(res)
        return res
def close(self):
    print('关闭了！')
    self.cur.close()
    self.coon.close()

封装操作oracle

import cx_Oracle
class MyOracle:#操作oracle数据库
    def __init__(self,username,password,host,port,instance):
        try:
            Log.info('连接oracle数据库')
            self.conn = cx_Oracle.connect("%s/%s@%s:%s/%s" % (username,password,host,port,instance))
            self.cursor = self.conn.cursor()
        except Exception as e:
            Log.error("数据库连接出错了！", e)
    def execute(self,sql):
        try:
            self.cursor.execute(sql)
            self.conn.commit()
        except Exception as e:
            Log.error("sql语句%s出错了！"%sql, e)

    def fetchone(self,sql):
        try:
            self.cursor.execute(sql)
        except Exception as e:
            Log.error("sql语句%s出错了！"%sql, e)
        else:
            return self.cursor.fetchone()

    def fetchall(self, sql):
        try:
            self.cursor.execute(sql)
        except Exception as e:
            Log.error('sql语句有误！%s' % e)
        else:
            return self.cursor.fetchall()

    def table_exists(self, table_name):
        sql = "select count(*) from user_tables where table_name =upper('%s')" % table_name
        if self.fetchone(sql):
            return True

    def close(self):
        self.cursor.close()
        self.conn.close()

网络编程：抓取一个群里的qq头像

import requests,pymongo,os

url = "https://qun.qq.com/cgi-bin/qun_mgr/search_group_members"

data = {"gc":728755825,"st":0,"end":200,"sort":0,"bkn":729730748}
header = {'Cookie':'pgv_pvi=4788783104; pgv_si=s6143795200; _qpsvr_localtk=0.862307479956725; pt2gguin=o1334933924; uin=o1334933924; skey=@kGLYaQbAR; ptisp=cnc; RK=TxDF2YA1bL; ptcz=91d386bcdfa51982aaa3605162d022ecf50b82dde22714d669df3d7fe14221b0; p_uin=o1334933924; pt4_token=5-Lm7rK62Wis6IJSPFU6mlTKzxfBkEe*xNqd45Vbuyc_; p_skey=hugzXms-cMfHsaJLZI47*L3qs0y4ChTV2jLXmF2HMxw_'}

res = requests.post(url=url,data=data,headers=header)
mems = res.json().get("mems")#?

client = pymongo.MongoClient(host="ip",port=27017)
db = client['qq_group']
table = db['zjr']

for i in mems:
    mem = {
        "qq":i.get("uin"),
        "gender":i.get("g"),
        "nick":i.get("nick"),
        "card":i.get("card"),
        "qage":i.get("qage")
    }
    if mem.get("gender") == 0:
        mem['gender'] = "男"
    elif mem.get("gender") == 1:
        mem['gender'] = "女"
    else:
        mem['gender'] = "未知"

    if mem.get("card") == "":
        mem['card'] = "没有群名片"

    table.insert_one(mem)
    qq="http://q4.qlogo.cn/g?b=qq&nk={0}&s=140"
    pics = requests.get(qq.format(mem.get("qq")))
    abs_path = os.path.join()#?
    with open(str(mem.get("qq"))+".jpg","wb") as f:
        f.write(pics.content)