Python Foundation 12th Day

A: Three-level menu exit method (the use of tag)

tag=True whiletag:Print('Level1') Choice=input ('Level1>>:'). Strip ()ifChoice = ='quit': Break    ifChoice = ='Quit_all': Tag =False whiletag:Print('Level2') Choice=input ('Level2>>:'). Strip ()ifChoice = ='quit': Break        ifChoice = ='Quit_all': Tag =False whiletag:Print('Level3') Choice= Input ('Level3>>:'). Strip ()ifChoice = ='quit': Break            ifChoice = ='Quit_all': Tag=false

II: Processing of documents (increase and deletion of search)

ImportOSdefFile_handler (backend_data,res='None', type='Fetch'):    ifType = ='Fetch': With open ('Renkoupucha','R') as Read_f:tag=false#identify a Stateret=[]             forRead_lineinchRead_f:ifRead_line.strip () = = Backend_data:#Remove Career Spacetag=TrueContinue                ifTag andRead_line.startswith ('Backend'):                     Break                iftag:Print(read_line,end="') ret.append (read_line)returnretelifType = =' Change': With open ('Renkoupucha','R') as Read_f, open ('renkoupucha_new','W') as Write_f:tag=False Has_write=False forRead_lineinchRead_f:ifRead_line.strip () = =Backend_data:tag=TrueContinue                ifTag andRead_line.startswith ('Backend'): Tag=Falseif  nottag:write_f.write (read_line)Else:                    if  notHas_write: forRecordinchRes:write_f.write (record) Has_write=True Os.rename ('Renkoupucha','Renkoupucha.bak') Os.rename ('renkoupucha_new','Renkoupucha') Os.remove ('Renloupucha.bak')defFetch (data): Backend_data='Backend%s'%DatareturnFile_handler (backend_data)defAdd ():PassdefChange (data):#print (' This is the modification function ')    Print('the data entered by the user is', data)#Data[0] #文档当中的一条记录backend=data[0]['Backend'] Backend_data='Backend%s'%Backend old_server_recored='%s Server%s%s weight%s Maxconn%s'%(' '*8,data[0]['Record']['Server'], data[0]['Record']['Server'], data[0]['Record']['Weight'], data[0]['Record']['Maxconn'],) new_server_recored='%s Server%s%s weight%s Maxconn%s'% (' '* 8, data[1]['Record']['Server'], data[1]['Record']['Server'], data[1]['Record']['Weight'], data[1]['Record']['Maxconn'],)    Print('the record that the user wants to modify is', old_server_recored) Res= Fetch (data[0]['Backend'])    Print(RES)if  notResorOld_server_recored not inchRes:return 'Modify record does not exist'    Else: Index=Res.index (old_server_recored) Res[index]=new_server_recored#Modified ListRes.insert ('%s\n'%backend_data) res.insert (0,'%s\n'%backend_data) File_handler (backend_data,res=res,type=' Change')defDelete ():Passif __name__=='__main__': Msg=" "1: Query 2: Add 3: Modify 4: Delete 5: Exit" "Msg_dic={        '1': Fetch,'2': Add,'3': Change,'4':d elete,} whileTrue:Print(msg) Choice=input ('Please enter your options:'). Strip ()if  notChoiceContinue        ifChoice = ='5': BreakData=input ('Please enter your data:'). Strip ()ifChoice! ='1': Data=eval (data) Res=Msg_dic[choice] (data)Print('Final Result', res)

Python Foundation 12th Day