C++ std::string length() 和 size() 成员函数
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std::string length() and size() member functions
提问by Naveen
I was reading the answers for this questionand found that there is actually a method called length()for std::string(I always used size()). Is there any specific reason for having this method in std::stringclass? I read both MSDN and CppRefernce, and they seem to indicate that there is no difference between size()and length(). If that is so, isn't it making more confusing for the user of the class?
我正在阅读这个问题的答案，发现实际上有一种方法length()需要std::string（我一直使用size()）。在std::string课堂上使用这种方法有什么具体原因吗？我阅读了 MSDN 和 CppRefernce，它们似乎表明size()和之间没有区别length()。如果是这样，是不是让课程的用户更加困惑？
回答by Todd Gamblin
As per the documentation, these are just synonyms. size()is there to be consistent with other STL containers (like vector, map, etc.) and length()is to be consistent with most peoples' intuitive notion of character strings. People usually talk about a word, sentence or paragraph's length, not its size, so length()is there to make things more readable.
根据文档，这些只是同义词。 size()在那里，以便与其他STL容器（如一致vector，map，等），并length()是要与大多数人的字符串的直观概念是一致的。人们通常谈论一个词、一个句子或一个段落的长度，而不是它的大小，所以这样做length()是为了使事情更具可读性。
回答by Alex Martelli
Ruby's just the same, btw, offering both #lengthand#sizeas synonyms for the number of items in arrays and hashes (C++ only does it for strings).
Ruby 是一样的，顺便说一句，提供#length和#size作为数组和散列中项目数的同义词（C++ 只对字符串这样做）。
Minimalists and people who believe "there ought to be one, and ideally only one, obvious way to do it" (as the Zen of Python recites) will, I guess, mostly agree with your doubts, @Naveen, while fans of Perl's "There's more than one way to do it" (or SQL's syntax with a bazillion optional "noise words" giving umpteen identically equivalent syntactic forms to express one concept) will no doubt be complaining that Ruby, and especially C++, just don't go far enough in offering such synonymical redundancy;-).
极简主义者和相信“应该有一种，理想情况下只有一种明显的方法来做到这一点”（正如 Python 之禅所言）的人，我想，我猜他们大多同意你的怀疑，@Naveen，而 Perl 的粉丝“有不止一种方法可以做到这一点”（或者 SQL 的语法带有无数可选的“噪音词”，给出了无数相同的语法形式来表达一个概念）无疑会抱怨 Ruby，尤其是 C++，只是不要走得太远足以提供这种同义的冗余；-)。
回答by Morten
When using coding practice tools(LeetCode) it seems that size() is quicker than length() (although basically negligible)
在使用编码练习工具（LeetCode）时，似乎 size() 比 length() 快（虽然基本上可以忽略不计）
回答by user7817690
length of string ==how many bits that string having, size==size of those bits, In strings both are same if the editor allocates size of character is 1 byte
字符串的长度 == 该字符串有多少位，大小==这些位的大小，如果编辑器分配的字符大小为 1 个字节，则在字符串中两者都是相同的
