【提高效率】C++使用map替代传统switch case

_Camille2023-10-26 7:05

switch case示例

c 复制代码

enum class ENTestType
{
    first = 1,
    second,
    third,
    forth
};

class Test
{
public:
    void testFun(ENTestType type)
    {
        switch (type)
        {
        case ENTestType::first:
            std::cout << "first" << std::endl;
            break;
        case ENTestType::second:
            std::cout << "first" << std::endl;
            break;
        case ENTestType::third:
            std::cout << "third" << std::endl;
            break;
        case ENTestType::forth:
            std::cout << "forth" << std::endl;
            break;
        default:
            break;
        }
    }
};

int main()
{
    auto t = std::make_unique<Test>();
    t->testFun(ENTestType::first);
    return 0;
}

使用map替代switch：

cpp 复制代码

class Test
{
public:
    Test()
    {
        _testMap[ENTestType::first] = []{
            std::cout << "first" << std::endl;
        };
        _testMap[ENTestType::second] = []{
            std::cout << "second" << std::endl;
        };
        _testMap[ENTestType::third] = []{
            std::cout << "third" << std::endl;
        };
        _testMap[ENTestType::forth] = []{
            std::cout << "forth" << std::endl;
        };
    }
public:
    std::map<ENTestType, std::function<void()>> _testMap;
};

int main()
{
    auto t = std::make_unique<Test>();
    t->_testMap[ENTestType::first]();
    return 0;
}