今天分享一些工作和生活中常用的代码，都是最基本的功能和操作，大部分都是经常出现的，而且很多都可以用直接或者干脆修改一下放到自己的项目中。喜欢的话记得收藏、关注、点赞哦。废话不多说，下面开始日期生成。很多时候我们需要批量生成日期。有很多方法。这里有两段代码可以获取过去N天的日期importdatetimedefget_nday_list(n):before_n_days=[]foriinrange(1,n+1)[::-1]:before_n_days.append(str(datetime.date.today()-datetime.timedelta(days=i)))returnbefore_n_daysa=get_nday_list(30)print(a)输出：['2021-12-23','2021-12-24','2021-12-25','2021-12-26','2021-12-27','2021-12-28','2021-12-29','2021-12-30','2021-12-31','2022-01-01','2022-01-02','2022-01-03','2022-01-04','2022-01-05','2022-01-06','2022-01-07','2022-01-08','2022-01-09','2022-01-10','2022-01-11','2022-01-12','2022-01-13','2022-01-14','2022-01-15','2022-01-16','2022-01-17','2022-01-18','2022-01-19','2022-01-20','2022-01-21']生成一个时间段内的日期importdatetimedefcreate_assist_date(datestart=None,dateend=None):#创建日期辅助表ifdatestartisNone:datestart='2016-01-01'ifdateendisNone:dateend=datetime.datetime.now().strftime('%Y-%m-%d')#转换为日期fo格式公式datestart=datetime.datetime.strptime(datestart,'%Y-%m-%d')dateend=datetime.datetime.strptime(dateend,'%Y-%m-%d')date_list=[]date_list.append(datestart.strftime('%Y-%m-%d'))whiledatestartPie:background_color_js=("newecharts.graphic.LinearGradient(0,0,0,1,""[{offset:0,color:'#c86589'},{offset:1,color:'#06a7ff'}],false)")c=(Pie(init_opts=opts.InitOpts(bg_color=JsCode(background_color_js))).add("",data,radius=["30%","75%"],center=["45%","50%"],rosetype="radius",label_opts=opts.LabelOpts(formatter="{b}:{c}"),).set_global_opts(title_opts=opts.TitleOpts(title=""),)returncrequests库调用统计，请求library是Python家族中被引用最多的第三方库，可见其地位之高！发送GET请求importrequestsheaders={'user-agent':'Mozilla/5.0(WindowsNT10.0;Win64;x64)AppleWebKit/537.36(KHTML,likeGecko)Chrome/96.0.4664.110Safari/537.36','cookie':'some_cookie'}response=requests.request("GET",url,headers=headers)发送POST请求importrequestspayload={}files=[]headers={'user-agent':'Mozilla/5.0(WindowsNT10.0;Win64;x64)AppleWebKit/537.36(KHTML,likeGecko)Chrome/96.0.4664.110Safari/537.36','cookie':'some_cookie'}response=requests.request("POST",url,headers=headers,data=payload,files=files)根据一定条件循环请求，比如根据生成日期defget_data(mydate):date_list=create_assist_date(mydate)url="https://test.test"files=[]headers={'用户代理t':'Mozilla/5.0(WindowsNT10.0;Win64;x64)AppleWebKit/537.36(KHTML,likeGecko)Chrome/96.0.4664.110Safari/537.36','cookie':''}fordindate_list:payload={'p':'10','day':d,'nodeid':'1','t':'itemsbydate','c':'node'}foriinrange(1,100):payload['p']=str(i)print("获取页面%s中%s的数据"%(d,str(i)))response=requests.request("POST",url,headers=headers,data=payload,files=files)items=response.json()['data']['items']ifitems:save_data(items,d)else:breakPython操作各种数据库操作Redis连接Redisimportredisdefredis_conn_pool():pool=redis.ConnectionPool(host='localhost',port=6379,decode_responses=True)rd=redis.Redis(connection_pool=pool)returnrd写入Redisfromredis_connimportredis_conn_poolrd=redis_conn_pool()rd.set('test_data','mytest')操作MongoDBconnectionMongoDBfrompymongoimportMongoClientconn=MongoClient("mongodb://%s:%s@ipaddress:49974/mydb"%('username','password'))db=conn.mydbmongo_collection=db.mydata批量插入数据res=requests.get(url,params=query).json()commentList=res['data']['commentList']mongo_collection.insert_many(commentList)操作MySQL连接MySQLimportMySQLdb#打开数据库连接db=MySQLdb.connect("localhost","testuser","test123","TESTDB",charset='utf8')#使用cursor()方法获取操作cursorcursor=db.cursor()执行SQL语句#使用execute方法执行SQL语句cursor.execute("SELECTVERSION()")#使用fetchone()方法获取一条数据data=cursor.fetchone()print"Databaseversion:%s"%data#关闭数据库连接db.close()输出：数据库版本：5.0。45.本地文件整理整理文件涉及到很多要求。我这里分享的是将多个本地CSV文件整合到一个文件中。将熊猫导入为pdimportosdf_list=[]foriinos.listdir():if"csv"ini:day=i.split('.')[0].split('_')[-1]df=pd.read_csv(i)df['day']=daydf_list.append(df)df=pd.concat(df_list,axis=0)df.to_csv("total.txt",index=0)多线程代码的实现方式有很多种，我们可以选择最熟悉最方便的方式导入threadingimporttimeexitFlag=0classmyThread(threading.Thread):def__init__(self,threadID,name,delay):threading.Thread.__init__(self)self.threadID=threadIDself.name=nameself.delay=delaydefrun(self):print("Startthread:"+self.name)print_time(self.name,self.delay,5)print("退出线程:"+self.name)defprint_time(threadName,delay,counter):whilecounter:ifexitFlag:threadName.exit()time.sleep(delay)print("%s:%s"%(threadName,time.ctime(time.time())))counter-=1#创建一个新线程thread1=myThread(1,"Thread-1",1)thread2=myThread(2,"Thread-2",2)#开启新线程thread1.start()thread2.start()thread1.join()thread2.join()print("退出主线程")异步编程代码异步爬取网站importasyncioimportaiohttpimportaiofilesasyncdefget_html(session,url):尝试：与se异步会话。get(url=url,timeout=8)作为响应：ifnotresp.status//100==2:print(resp.status)print("Crawling",url,"Anerroroccurred")else:resp.encoding='utf-8'text=awaitresp.text()returntextexceptExceptionase:print("Anerroroccurred",e)awaitget_html(session,url)使用异步请求后，对应的文件保存也需要使用异步，即一处异步，处处异步asyncdefdownload(title_list,content_list):asyncwithaiofiles.open('{}.txt'.format(title_list[0]),'a',encoding='utf-8')asf:awaitf.write('{}'.format(str(content_list)))以上是我平时使用最多的代码片段，希望对大家有所帮助，今天分享的内容就这些了，喜欢的话点个赞吧
