<p>假设我们需要遍历id,对于每个id,遍历大写拉丁字母,我们可以编写</p>
<pre><code>from string import ascii_uppercase
def get_urls(number_stop):
url = "http://resources.afaqs.com/index.html?id={}&category=AD+Agencies&alpha={}"
urls = []
for number in range(1, number_stop):
for letter in ascii_uppercase:
urls.append(url.format(number, letter))
return urls
</code></pre>
<p>或者使用<a href="https://docs.python.org/2/glossary.html#term-generator" rel="nofollow noreferrer">generator</a></p>
<pre><code>from string import ascii_uppercase
def generate_urls(number_stop):
url = "http://resources.afaqs.com/index.html?id={}&category=AD+Agencies&alpha={}"
for number in range(1, number_stop):
for letter in ascii_uppercase:
yield url.format(number, letter)
</code></pre>
<p>或者最后使用generator&;<a href="https://docs.python.org/2/library/itertools.html#itertools.product" rel="nofollow noreferrer">^{<cd1>}</a>除去多余的循环</p>
<pre><code>from itertools import product
from string import ascii_uppercase
def generate_urls(number_stop):
url = "http://resources.afaqs.com/index.html?id={}&category=AD+Agencies&alpha={}"
for number, letter in product(range(1, number_stop),
ascii_uppercase):
yield url.format(number, letter)
</code></pre>