我如何编写代码以使用 python 编辑 txt 文件中的字符

Question

它在询问旧代码后保持停止运行并清除我的 roti canai 文件。那么我能为它做些什么呢（甚至正在更改所有代码）

def modify_roti_canai():
    print("\n*-- Modify Roti Canai Menu --*\n")
    file = open("roticanai", "r+")
    print(file.read())
    old_code = input("Enter a Item Code for Modifying (e.g. RC01): ")
    if len(old_code) == 4:
        new_code = input("New Food Item Code: ")
        new_name = input("New Food Item Name: ")
        new_price = input("New Food Item Price: ")
        file.write(new_code + "," + new_name + "," + new_price + "\n")
    else:
        print("Item Code Not Existed, Please try again!")
    file.close()

*在我的 roticanai 文件中存在很少的记录：

RC01,ROTI CANAI KOSONG,1.60
RC02,ROTI CANAI SUSU,3.90
RC03,ROTI CANAI CHEESE,4.50
RC04,ROTI CANAI PLANTA,3.90
RC05,ROTI CANAI TISSUE,4.50

Answer 1

s 是一个空字符串。如果您将长度（即 0）与 4 进行比较，则 if 语句的计算结果为 False。它不会将数据添加到“temp.txt”文件。它将一个空文件重命名为“roticanai”。

Answer 2

根据需要重命名文件名 **使用相同的文件名，不需要临时文件

def modify_roti_canai():
    print("\n*-- Modify Roti Canai Menu --*\n")

    with open("test.txt", "r") as file:
        #Gets each line of the file as list item
        data = [line.rstrip() for line in file.readlines()]
        print(data)

    #separates codes from data
    codes= [x.split(',')[0] for x in data]
    print(codes)

    old_code = input("Enter a Item Code for Modifying (e.g. RC01): ")

    if len(old_code) == 4:
        #removes the old code line from data using the index of entered code
        data.pop(codes.index(old_code))
        new_code = input("New Food Item Code: ")
        new_name = input("New Food Item Name: ")
        new_price = input("New Food Item Price: ")
        new_data = f"{new_code},{new_name},{new_price}"
        #appends new data to the data list
        data.append(new_data)
        #Writes the data list to file
        with open('test.txt','w') as file:
            for e in data:
                file.write(e + '\n')
            print(file.read())
    else:
        print("Item Code Not Existed, Please try again!")

我如何编写代码以使用 python 编辑 txt 文件中的字符

How can i code for edit a character in a txt file with python

python

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