c++ - 如何将 std::wstring 转换为数字类型(int、long、float)？

Question

将 std::wstring 转换为数字类型(例如 int、long、float 或 double)的最佳方法是什么？

Answer 1

C++0x 引入了 following functions在<string> :

int                stoi  (const wstring& str, size_t* idx = 0, int base = 10);
long               stol  (const wstring& str, size_t* idx = 0, int base = 10);
unsigned long      stoul (const wstring& str, size_t* idx = 0, int base = 10);
long long          stoll (const wstring& str, size_t* idx = 0, int base = 10);
unsigned long long stoull(const wstring& str, size_t* idx = 0, int base = 10);

float       stof (const wstring& str, size_t* idx = 0);
double      stod (const wstring& str, size_t* idx = 0);
long double stold(const wstring& str, size_t* idx = 0);

idx是一个可选的空指针，指向 str 内的转换结束(由转换函数设置)。