重载函数的实现

Question

在我的头文件中,我有这个:

std::string StringExtend(const std::string Source, const unsigned int Length, const bool Reverse);
std::string StringExtend(const std::string Source, const unsigned int Length);

在我的cpp文件中,我有这个:

std::string Cranberry::StringExtend(const std::string Source, const unsigned int Length, const bool Reverse)
{
    unsigned int StartIndex = (Source.length() - 1) * Reverse;
    short int  Increment = 1 - (Reverse * 2);

    int Index = StartIndex;

    std::string Result;

    while (Result.length() < Length)
    {
        if (Reverse) Result = Source.at(Index) + Result;
        else Result += Source.at(Index);

        Index += Increment;

        if (!InRange(Index, 0, Source.length() - 1)) Index = StartIndex;
    }

    return Result;
}

std::string Cranberry::StringExtend(const std::string Source, const unsigned int Length)
{
    return StringExtend(Source, Length, false);
}

如您所见,函数的第二种形式与Reverse省略的参数完全相同.有没有办法压缩这个,还是我必须为每个表单都有一个函数原型和定义？

Answer 1

使用参数的默认Reverse参数.

std::string StringExtend(const std::string & Source, unsigned int Length, bool Reverse = false);

摆脱第二个功能:

std::string StringExtend(const std::string & Source, unsigned int Length);