Python：對于字典中的特定專案，繼續提示輸入，直到輸入格式正確

我希望我的代碼提示用戶輸入圖書詳細資訊，但如果他們沒有輸入正整數/小數或“N/A”作為評級和頁數，他們將被重新提示，直到他們輸入所以。用戶也可以在任何輸入提示下通過輸入“Q”作為輸入退出程式。最后，將填寫 add_details_dict 而不是將 None 作為所有鍵。這是我到目前為止所擁有的：

add_details_dict = {'title':None, 'author':None, 'language':None, 'publisher':None, 'category':None, 'rating':None, 'pages':None}
for key in add_details_dict.keys():
    prompt = "Enter the "   key   " of the book you want to add. To quit: Q)uit\n"
    current_input = input(prompt)
    if current_input == 'Q':
        break
    else:
        if key in ['rating', 'pages'] and current_input != 'N/A':
            try:
                add_details_dict[key] = float(current_input)
            except ValueError:
                print ("The ", key, " must be a positive and a whole number, decimal number, or 'N/A'.", sep='')
        else:
            add_details_dict[key] = current_input

問題是如果用戶沒有為評級/頁面輸入整數、小數或“N/A”。在通知用戶評分/頁數必須是整數、十進制數或“N/A”后，我希望程式回到 for 回圈當前迭代的開頭，即提示行，即current_input = 輸入（提示）。所以它會重新提示他們評分/頁面，如果他們再次搞砸，它將繼續重新提示，直到評分和頁面都是整數、小數或“N/A”。我希望固定代碼輸出這個：

Enter the title of the book you want to add. To quit: Q)uit:
sometitle
Enter the author of the book you want to add. To quit: Q)uit:
someauthor
Enter the language of the book you want to add. To quit: Q)uit:
English
Enter the publisher of the book you want to add. To quit: Q)uit:
somepublisher
Enter the category of the book you want to add. To quit: Q)uit:
somecategory
Enter the rating of the book you want to add. To quit: Q)uit:
nonsenserating
The rating must be a positive and a whole number, decimal number, or 'N/A'.
Enter the rating of the book you want to add. To quit: Q)uit:
5.7
Enter the pages of the book you want to add. To quit: Q)uit:
nonsensepages
The pages must be a positive and a whole number, decimal number, or 'N/A'.
Enter the pages of the book you want to add. To quit: Q)uit:
557

然后對于 add_details_dict，我應該得到以下資訊：

add_details_dict = {'title':'sometitle', 'author':'someauthor', 'language':'English', 'publisher':'somepublisher', 'category':'somecategory', 'rating':5.7, 'pages':557}

我很欣賞這個問題的修復，以便程式滿足上述結果。

uj5u.com熱心網友回復：

如果您為每個鍵添加一個回圈，并且僅break當用戶輸入一個合適的值時，那么提示將不斷出現，直到他們輸入可接受的內容。當然，break如果他們輸入 Q 將不起作用，因此您可以quit為此使用布爾變數：

add_details_dict = {'title':None, 'author':None, 'language':None, 'publisher':None, 'category':None, 'rating':None, 'pages':None}
quit = False
for key in add_details_dict.keys():
    while True:
        prompt = "Enter the "   key   " of the book you want to add. To quit: Q)uit\n"
        current_input = input(prompt)
        if current_input == 'Q':
            quit = True
            break
        else:
            if key in ['rating', 'pages'] and current_input != 'N/A':
                try:
                    add_details_dict[key] = float(current_input)
                    break
                except ValueError:
                    print ("The ", key, " must be a positive and a whole number, decimal number, or 'N/A'.", sep='')
            else:
                add_details_dict[key] = current_input
                break
    if quit:
        break

標籤：Python 字典 for循环 输入

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