004 classmates subject

look code

# Filename: classmates2.py
import os,pickle

class Friend:
    def __init__(self,name,age,phone):
        self.name=name
        self.age=age
        self.phone=phone

    def __str__(self):
        return '%s %d %s'%(self.name,self.age,self.phone)

class Main:
    flist=[]
    # data list
    isChange=False
    # tip change operating
    isStart=True
    # tip start
    source='classmates'
    # source data name
    
    def __init__(self):
        hasData=os.path.isfile(Main.source+'.data')
        hasTxt=os.path.isfile(Main.source+'.txt')
        if hasData:
            Main.readFile(self,Main.source+'.data')
        elif hasTxt:
            Main.readTxtFile(self,Main.source+'.txt')
            Main.save(self)
        else:
            Main.writeFile(self,Main.source+'.data')
        Main.isStart=False
 
    # Start
    def start(self):
        Main.readme(self)
        while True:
            cmd=input('Command:')
            if cmd in ['exit','quit','q']:
                break;
            elif cmd in ['show','sh']:
                Main.show(self)
            elif cmd.startswith('find'):
                Main.show(self,Main.find(self,cmd.split(',')[1:]))
            elif cmd.startswith('add'):
                Main.add(self,cmd.split(',')[1:])
            elif cmd.startswith('dele'):
                Main.delete(self,cmd.split(',')[1:])
            elif cmd in['clear','clr','c']:
                Main.clear(self)
            elif cmd in ['save','sa']:
                Main.save(self)
            elif cmd.startswith('export'):
                Main.export(self)
            else:
                print('Please try again!')
        print('exit')

    # Show data
    def show(self,data=None):
        if data==None:
            data=Main.flist[:]
        if len(data)==0:
            print('no result')
        else:
            if len(data)==1:
                print(data[0])
            else:
                print('list size %d:'%len(data))
                for item in data:
                    print(item)

    # Find data list by keys
    def find(self,keys):
        if len(keys)==0:
            return []
        else:
            tmplist=[]
            for fri in Main.flist:
                if (fri.name in keys) or (str(fri.age) in keys) or (fri.phone in keys):
                    tmplist.append(fri)
            return tmplist

    # Add data to flist
    def add(self,vals):
        if len(vals)==3:
            Main.flist.append(Friend(vals[0],int(vals[1]),vals[2]))
            Main.isChange=True
            if not Main.isStart:
                print('%s add success!'%vals[0])
        else:
            print('the add command arguments is error, it must following 3 argument.')

    # Delete data by keys
    def delete(self,keys):
        tmplist=Main.find(self,keys)
        if len(tmplist)==0:
            print('no reslt')
        else:
            Main.flist=[i for i in Main.flist if not (i in tmplist)]
            Main.isChange=True
            print('has delete')
            Main.show(self,tmplist)
    def clear(self):
        if len(Main.flist)==0:
            print('no need')
        else:
            Main.flist.clear()
            Main.isChange=True
            print('clear success')
            
    # Save data to local
    def save(self):
        if Main.isChange:
            Main.isChange=False
            Main.writeFile(self,Main.source+'.data')
            if not Main.isStart:
                print('save success')
        else:
            print('No change')
    # Write informat to the path file
    def writeFile(self,path):
        file=open(path,'wb')
        pickle.dump(Main.flist,file)
        file.close()
        
    # Read the path file
    def readFile(self,path):
        file=open(path,'rb')
        Main.flist=pickle.load(file)
        file.close()

    # Read the path text file
    def readTxtFile(self,path):
        file=open(path,encoding='utf-8')
        line=file.readline()
        while True:
            line=file.readline()
            if len(line)==0:
                break
            Main.add(self,line.strip().split(' '))
    
    # Export a text file
    def export(self,path=None):
        if not Main.isChange:
            print('No change')
            return
        
        if path==None:
            path=Main.source+'.txt'
        file=open(path,'w',encoding='utf-8')
        file.write(Main.parseStr(self))
        file.close()

        os.system(path)
        print('exprot success')

    # Parse list to str
    def parseStr(self):
        rst='list:\n'
        for fri in Main.flist:
            rst+=str(fri)+'\n'
        return rst
    
    # User's manual
    def readme(self):
        print('You can input up command:')
        print('  exit/quit/q:exit the program')
        print('  show/sh:show the list')
        print('  find:find list by keys')
        print('  add:add new friend information')
        print('  dele:delete by keys')
        print('  clear/clr/c:clear the list')
        print('  save/sa:save the result')
        print('  export:export a text file and view the file')
        pass

main=Main()
main.start()