如何将十六进制字符串转换为unsigned char数组？

#include <iostream>
#include <string>
#include <vector>

std::vector<unsigned char> hexStringToUnsignedCharArray(const std::string& hexString) {
    std::vector<unsigned char> result;

    // 检查十六进制字符串长度是否为偶数
    if (hexString.length() % 2 != 0) {
        std::cout << "Invalid hex string length." << std::endl;
        return result;
    }

    // 将十六进制字符串转换为unsigned char数组
    for (size_t i = 0; i < hexString.length(); i += 2) {
        std::string byteString = hexString.substr(i, 2);
        int decimalValue = std::stoi(byteString, nullptr, 16);
        unsigned char byteValue = static_cast<unsigned char>(decimalValue);
        result.push_back(byteValue);
    }

    return result;
}

int main() {
    std::string hexString = "48656C6C6F20576F726C64"; // 十六进制字符串
    std::vector<unsigned char> byteArray = hexStringToUnsignedCharArray(hexString);

    // 打印unsigned char数组中的值
    for (const auto& byte : byteArray) {
        std::cout << static_cast<int>(byte) << " ";
    }
    std::cout << std::endl;

    return 0;
}