Python 2.7 指向文本插入python文件io

我需要一些代码，我一直在工作的帮助

def themain():
    print "============================================================================"
    lol = raw_input("""Would you like to add new stock prices to a company (add)/read all of the previous
stock prices(read)(note that the newest stock price will be at the far right while
the oldest stock price will be located at the far left)/or add a new company(add new): """)
    if lol.lower() == "add":
        def main():
            print "============================================================================"
            lol = raw_input("Insert Name of Company: ")
            print "Are you sure you typed the company name in right? Answer with yes or no. : "  + lol
            lol2 = raw_input()
            if lol2 == "yes":
                fo = open(lol.lower() + ".txt", "a")
                main = raw_input("Type in new stock price: ")
                fo.write(main + ":");
                fo.close()
                themain()
            elif lol2 == "no":
                main()
            else:
                print "Please type either yes or no"
                themain()
        main()
    elif lol.lower() == "read":
        def main2():
                def read():
                    print "============================================================================"
                    lol = raw_input("Insert Name of Company: ")
                    try:
                        fo = open(lol.lower() + ".txt", "r+")
                        read = fo.read();
                        print read
                        fo.close()
                    except IOError:
                        print "Not a valid company please try again"
                        main2()
                    themain()
                read()
        main2()
    elif lol.lower() == "add new":
        def addnew():
            print "============================================================================"
            lol = raw_input("Insert the name of the new company: ")
            print "Are you sure you typed in the name correctly?"
            print lol
            print "Please say either yes or no: "
            response = raw_input()
            if response.lower() == "yes":
                fo = open(lol.lower() + ".txt", "a+")
                fo.write(lol.lower + ":")
                fo.close()
                themain()
            elif response.lower() == "no":
                addnew()
            else:
                print "Please say either yes or no"
                themain()
        addnew()
    else:
        print "Please say either read, add new, or add"
        themain()
themain()

我想粘贴代码后解释起来可能会更容易。因此，在创建新业务时，它会创建文件并将业务名称添加到文件的前面。然后，当你在业务中添加新股票时，它会将它们追加到末尾。例如，它将其放入文本文件Business:oldeststock:newerstock:neweststock。我想做的是让它按照这个顺序运行：neweststock:newerstock:oldeststock。我似乎找不到我该怎么做。我试着寻找，但当我对梅因这样做的时候，结果并不是很好

def main():
        print "============================================================================"
        lol = raw_input("Insert Name of Company: ")
        print "Are you sure you typed the company name in right? Answer with yes or no. : "  + lol
        lol2 = raw_input()
        if lol2 == "yes":
            fo = open(lol.lower() + ".txt", "r+")
            main = raw_input("Type in new stock price: ")
            fo.seek(len(fo.name) - 4)
            fo.write(":" + main);
            fo.close()
            themain()
        elif lol2 == "no":
            main()
        else:
            print "Please type either yes or no"
            themain()
    main()

---

我所做的是添加fo.seeklenfo.name-4，这样它将查找名称末尾减去扩展名.txt，但它所做的只是替换已经存在的数字。有没有什么方法可以添加到它，但从那一点开始，它向下移动其他数字并插入到那里，或者我完全认为这是错误的，有一个简单的解决方案，已经暗示了我三个小时；-

不是在r+模式下打开文本文件，而是在a+模式下打开文本文件并写入该文件是一种选择吗

所以看起来是这样的：

#Editing the if condition only

 if lol2 == "yes":
   #Indentation is off for some reason, this should be indented below the if statement

    fo = open(lol.lower() + ".txt", "r+")
    string = fo.read()
    fo.close()

    # Finding where the colon is located
    index = string.find(":")
    # Slicing where the :new:old is
    aStr = string[index:]
    main = raw_input("Type in new stock price: ")
    # Putting the string slices together
    main = string[:index]+":"+userinput+aStr
    fo = open("test.txt","w+")
    fo.write(main) #This would add the raw input at the end of the file.          
    fo.close()
    themain()

---

你有没有考虑过。。。标准序列化选项？json、pickle、shelve等等？我从没听说过，但我可以去看看。顺便说一句，我不熟悉python。我不能使用pickle，因为我需要将它保存到txt文件中，因为java程序正在读取txt文件中的内容。然后使用json，这是事实上的跨平台序列化协议。或者使用lxml模块创建XML。java喜欢XML：在文件中间添加一些东西，你必须从文件中读取所有数据，并用新数据写入新文件。使用XML、JSON或CSV，读/写文件更容易。这会将文件添加到末尾，但我需要以下格式的文件：Business:neweststock:newerstock:oldeststock。那会是最新的。哎呀，我的错。我将编辑上面的代码。希望这有助于：-