size_t CMyStr::_myStrlen(char const * srcStr)    {        size_t len = 0;        if (srcStr != NULL)        {            while (*(srcStr + len) != '\0')            {                len++;            }        }        return len;    } //字符串的最后为'\0'的问题，字符串的长度包括'\0'

 

//字符串之数字处理    CMyStr(int i)    {        int tempVal = i;        bool isFu = false;        if (tempVal < 0)        {            len = 2; // \0  -号            isFu = true;            tempVal = -tempVal;        }        else            len = 1; // \0        while (tempVal)        {            tempVal /= 10;            len++;        }        pStr = new char[len];        *(pStr + len - 1) = '\0';        if (ifFul)        {            tempVal = -i;        }        else            tempVal = i;        int index = 0;        while (tempVal)        {            int temp = tempVal % 10;            *(pStr + len - 2 - index) = temp + '0'; //转换为字符类型            tempVal /= 10;            index++;        }        if (isFu)            *pStr = '-';    }

 

//字母ASCII码  A--65  a--97    char *str;    int counter[26];    void doc::count()    {        for (int i = 0; i < length; i++)        {            if (str[i] >= 'a' && str[i] <= 'z')                counter[str[i] - 'a']++;            if (str[i] >= 'A' && str[i] <= 'Z')                counter[str[i] - 'A']++;        }        for (int index = 0; index < 26; ++index)            cout << (char)(index + 65) << " or " << (char)(index + 97) << " 出现的次数是：" << counter[index] << endl;