擅长:python、mysql、java
<p>正如<a href="https://stackoverflow.com/users/367273/npe">NPE</a>在本<a href="https://stackoverflow.com/questions/6269765/what-does-the-b-character-do-in-front-of-a-string-literal">question</a>中所述,引用<a href="https://docs.python.org/2/reference/lexical_analysis.html#string-literals" rel="nofollow noreferrer">Python 2.x documentation</a>:</p>
<blockquote>
<p>A prefix of 'b' or 'B' is ignored in Python 2; it indicates that the literal should become a bytes literal in Python 3 (e.g. when code is automatically converted with 2to3). A 'u' or 'b' prefix may be followed by an 'r' prefix.</p>
</blockquote>
<p>报告指出:</p>
<blockquote>
<p>Bytes literals are always prefixed with 'b' or 'B'; they produce an instance of the bytes type instead of the str type. They may only contain ASCII characters; bytes with a numeric value of 128 or greater must be expressed with escapes.</p>
</blockquote>