std :: string to char * [英] std::string to char*

问题描述

我想将 std :: string 转换为 char * 或 char [] 数据类型。

I want to convert a std::string into a char* or char[] data type.

std::string str = "string";
char* chr = str;

结果：错误：无法将'std :: string'转换为'char' ...

Results in: "error: cannot convert ‘std::string’ to ‘char’ ...".

有什么方法可以做到这一点？

What methods are there available to do this?

推荐答案

它不会自动转换（感谢上帝）。您必须使用 c_str（）方法获取C字符串版本。

It won't automatically convert (thank god). You'll have to use the method c_str() to get the C string version.

std::string str = "string";
const char *cstr = str.c_str();

注意，它返回一个 const char * ;您不能更改由 c_str（）返回的C风格字符串。如果你想处理它，你必须先复制它：

Note that it returns a const char *; you aren't allowed to change the C-style string returned by c_str(). If you want to process it you'll have to copy it first:

std::string str = "string";
char *cstr = new char[str.length() + 1];
strcpy(cstr, str.c_str());
// do stuff
delete [] cstr;

或在现代C ++中：

std::vector<char> cstr(str.c_str(), str.c_str() + str.size() + 1);

这篇关于std :: string to char *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！