c++ - Cannot convert from string to hexadecimal

Question

Possible Duplicate:
C++ convert hex string to signed integer

I have the string line which is a hexadecimal number say like 12ab43c..(but I have read it as a string) and I would like to pass it to an unsigned char* linehex or directly to a hexadecimal so I can later use it in my program for further computations. Which is the most efficient way to do this?

Answer 1

最简单的可能是将其作为数字读取，而不是将其作为字符串读取，然后进行转换。例如：

some_stream >> std::hex >> your_number;

快速演示代码：

#include <iostream>

int main() {    
    int x;

    std::cin >> std::hex >> x;

    std::cout << x << "\n";
    return 0;
}

输入：ff
输出：255