擅长:python、mysql、java
<p>我想我应该用一个生成器表达式:</p>
<pre><code>(line for line in open('file.txt') if line.startswith('?'))
</code></pre>
<p>完整的程序如下所示:</p>
<pre><code>lines = (line for line in open('file.txt') if line.startswith('?'))
print ''.join(lines)
</code></pre>