如何初始化带有长度的std :: string？ [英] How to initialize an std::string with a length?

问题描述

如果字符串的长度是在编译时确定的，我该如何正确初始化它？

If a string's length is determined at compile-time, how can I properly initialize it?

#include <string>
int length = 3;
string word[length]; //invalid syntax, but doing `string word = "   "` will work
word[0] = 'a'; 
word[1] = 'b';
word[2] = 'c';

...以便我可以做这样的事情？

...so that i can do something like this?

示例： http://ideone.com/FlniGm

我这样做的目的是因为我有一个循环，可以将字符从另一个字符串的某些区域复制到新字符串中。

My purpose for doing this is because I have a loop to copy characters from certain areas of another string into a new string.

推荐答案

字符串是可变的，并且其长度可以在运行时更改。但是，如果必须具有指定的长度，则可以使用填充构造函数：
http://www.cplusplus.com/reference/string/string/string/

A string is mutable and it's length can changed at run-time. But you can use the "fill constructor" if you must have a specified length: http://www.cplusplus.com/reference/string/string/string/

std::string s6 (10, 'x');

s6 现在等于 xxxxxxxxxx 。

这篇关于如何初始化带有长度的std :: string？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！