c++使用binstr_to_value将二进制字符串转换为指定类型数值

#include <string>
#include <algorithm>
#include <iostream>

template<typename T>
T binstr_to_value(const std::string &sval)
{
    T v {};

    size_t bitcnt = static_cast<int>(sizeof(v) * 8);
    size_t strlen = sval.length();

    if (strlen > 0)
    {
        const char *d = sval.c_str() + strlen - 1;
        size_t fillcnt = std::min(bitcnt, strlen);

        for (size_t i = 0; i < fillcnt; i++, d--)
        {
            T mask = (1 << i);
            if (*d == '1')
                v |= mask;
        }
    }

    return v;
}

template<>
float binstr_to_value(const std::string &sval)
{
    return 0.0f;
}

template<>
double binstr_to_value(const std::string &sval)
{
    return 0.0;
}

int main()
{
    char v1 = binstr_to_value<char>("1111111101");
    short v2 = binstr_to_value<short>("1100111100111011");
    int v2 = binstr_to_value<int>("1101100011111");
    float v3 = binstr_to_value<float>("1011000111001");
}

第二版

/*
**  binstr_to_value
**  将二进制字符串（可包含空白字符）转换为目标类型的数值
**  当目标类型为浮点数时，返回0.0
**  reverse：指示是否反转位表示
*/
template<typename T>
T binstr_to_value(std::string sval, bool reverse = false)
{
    T v {};

    sval.erase(
        std::remove_if(sval.begin(), sval.end(), isspace),
        sval.end()
    );

    if (reverse)
    {
        std::reverse(sval.begin(), sval.end());
    }

    size_t bitcnt = static_cast<int>(sizeof(v) * 8);
    size_t strlen = sval.length();

    if (strlen > 0)
    {
        const char *d = sval.c_str() + strlen - 1;
        size_t fillcnt = std::min(bitcnt, strlen);

        for (size_t i = 0; i < fillcnt; i++, d--)
        {
            T mask = (1 << i);
            if (*d == '1')
                v |= mask;
        }
    }

    return v;
}

template<>
float binstr_to_value(std::string sval, bool)
{
    return 0.0f;
}

template<>
double binstr_to_value(std::string sval, bool)
{
    return 0.0;
}

int main()
{
    // 二进制字符串包含空白字符
    char v1 = binstr_to_value<char>("1111 111 101");        // -3
    char v2 = binstr_to_value<char>("111 111 101", true);   // 127
}