Convert hex string to unsigned char in C++

Question

How can I convert it? And I want the converted result to 1.

#include <iostream>
#include <string>

int main(int argc, const char * argv[]) {
    std::string s = "0x00";
    // insert code here...
    unsigned char* str_hex = (unsigned char*)s.c_str();
    
    unsigned char target = 0x00;
    
    std::cout << "result: " << (*str_hex == target) << "\n";
    return 0;
}

Answer 1

Like this: // #include <string>

std::string s = "0x4A";
unsigned char ch = std::stoul(s, nullptr, 16); // 'J' (Since C++11)

Or like this: // #include <cstdio>

std::string s = "0x4B";
unsigned char ch = '\0';
sscanf(s.c_str(), "%x", &ch); // 'K' (C library function)