將字符串轉換為字典列表 Python3

Question

使用 Python 3.5.2，將字符串轉換為字典列表的最佳方法是什么？

我正在抓取一個站點，以下內容作為長度為 1 的列表返回：

（為了可讀性而格式化）

[
{"variation_id":573,"variation_is_visible":true,"variation_is_active":true,"is_purchasable":true,"display_price":1099,"display_regular_price":1099,"attributes":{"attribute_pa_size":"king"},"image_src":"","image_link":"","image_title":"","image_alt":"","image_caption":"","image_srcset":"","image_sizes":"","price_html":"<span class=\"price\"><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&#82;<\/span>1,099.00<\/span><\/span>","availability_html":"<p class=\"stock in-stock\">2 in stock<\/p>","sku":"6006239211693","weight":" kg","dimensions":"","min_qty":1,"max_qty":2,"backorders_allowed":false,"is_in_stock":true,"is_downloadable":false,"is_virtual":false,"is_sold_individually":"no","variation_description":""},

{"variation_id":574,"variation_is_visible":true,"variation_is_active":true,"is_purchasable":true,"display_price":989,"display_regular_price":989,"attributes":{"attribute_pa_size":"queen"},"image_src":"","image_link":"","image_title":"","image_alt":"","image_caption":"","image_srcset":"","image_sizes":"","price_html":"<span class=\"price\"><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&#82;<\/span>989.00<\/span><\/span>","availability_html":"<p class=\"stock in-stock\">2 in stock<\/p>","sku":"6006239211686","weight":" kg","dimensions":"","min_qty":1,"max_qty":2,"backorders_allowed":false,"is_in_stock":true,"is_downloadable":false,"is_virtual":false,"is_sold_individually":"no","variation_description":""},

{"variation_id":575,"variation_is_visible":true,"variation_is_active":true,"is_purchasable":true,"display_price":949,"display_regular_price":949,"attributes":{"attribute_pa_size":"double"},"image_src":"","image_link":"","image_title":"","image_alt":"","image_caption":"","image_srcset":"","image_sizes":"","price_html":"<span class=\"price\"><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&#82;<\/span>949.00<\/span><\/span>","availability_html":"<p class=\"stock in-stock\">2 in stock<\/p>","sku":"6006239211679","weight":" kg","dimensions":"","min_qty":1,"max_qty":2,"backorders_allowed":false,"is_in_stock":true,"is_downloadable":false,"is_virtual":false,"is_sold_individually":"no","variation_description":""}

]

我嘗試將其轉換為 str，將其分配給“s”，然后使用 json.loads(s)，但這不起作用。

我想要一個列表對象，我可以通過它訪問類似以下內容的值：

for item in form_data_returned:
    print item['variation_id']  # prints 573  574  575

謝謝

Answer 1

from collections import defaultdict

# Set aliases for `true` and `false` in the output so
# we won't get NameError exceptions thrown.
true = True
false = False

raw = [
{"variation_id":573,"variation_is_visible":true,"variation_is_active":true,"is_purchasable":true,"display_price":1099,"display_regular_price":1099,"attributes":{"attribute_pa_size":"king"},"image_src":"","image_link":"","image_title":"","image_alt":"","image_caption":"","image_srcset":"","image_sizes":"","price_html":"<span class=\"price\"><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&#82;<\/span>1,099.00<\/span><\/span>","availability_html":"<p class=\"stock in-stock\">2 in stock<\/p>","sku":"6006239211693","weight":" kg","dimensions":"","min_qty":1,"max_qty":2,"backorders_allowed":false,"is_in_stock":true,"is_downloadable":false,"is_virtual":false,"is_sold_individually":"no","variation_description":""},

{"variation_id":574,"variation_is_visible":true,"variation_is_active":true,"is_purchasable":true,"display_price":989,"display_regular_price":989,"attributes":{"attribute_pa_size":"queen"},"image_src":"","image_link":"","image_title":"","image_alt":"","image_caption":"","image_srcset":"","image_sizes":"","price_html":"<span class=\"price\"><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&#82;<\/span>989.00<\/span><\/span>","availability_html":"<p class=\"stock in-stock\">2 in stock<\/p>","sku":"6006239211686","weight":" kg","dimensions":"","min_qty":1,"max_qty":2,"backorders_allowed":false,"is_in_stock":true,"is_downloadable":false,"is_virtual":false,"is_sold_individually":"no","variation_description":""},

{"variation_id":575,"variation_is_visible":true,"variation_is_active":true,"is_purchasable":true,"display_price":949,"display_regular_price":949,"attributes":{"attribute_pa_size":"double"},"image_src":"","image_link":"","image_title":"","image_alt":"","image_caption":"","image_srcset":"","image_sizes":"","price_html":"<span class=\"price\"><span class=\"woocommerce-Price-amount amount\"><span class=\"woocommerce-Price-currencySymbol\">&#82;<\/span>949.00<\/span><\/span>","availability_html":"<p class=\"stock in-stock\">2 in stock<\/p>","sku":"6006239211679","weight":" kg","dimensions":"","min_qty":1,"max_qty":2,"backorders_allowed":false,"is_in_stock":true,"is_downloadable":false,"is_virtual":false,"is_sold_individually":"no","variation_description":""}

]

# keys being a set ensures that every key occurs only once.
keys = set()

# Initializing form_data_returned as a defaultdict allows
# us to access keys that are not already in form_data_returned.
# For example form_data_returned['weight'].append('kg') would throw
# KeyError exception for an empty form_data_returned had we declared
# it as a normal dict().
form_data_returned = defaultdict(list)

for dictionary in raw:
    keys.update(dictionary.keys())
    for key in keys:
        form_data_returned[key].append(dictionary[key])

我們現在可以通過鍵檢索數據：

print(form_data_returned['variation_id'])
>>> [573, 574, 575]

Answer 2

使用re模塊對字符串進行預處理，然后使用json模塊將其解析為字典。

假設您已將數據轉換為字符串，並且您知道某些規則適用於內容*，您可以嘗試以下操作：

str = '...'

escaped = re.sub('(?<=[^,:{}])(\\\")(?=[^,:{}])','\\"',str)

dict = json.loads(escaped)

正則表達式(?<=[^,:{}])(\\\\\\")(?=[^,:{}])將解析字符串並識別所有字符"前面沒有',' , ':' , '{', '}'或之后是相同的，從而使"在數據中的字符串可以被正確轉義。

*根據規則，我的意思是，您必須知道，所使用的正則表達式找到了正確的字符 - 如果數據源可以提供這種一致性，則上面的代碼應該可以工作（擴展(?<=[^,:{}])和(?=[^,:{}])部分具有必要的字符以匹配所有數據