C++ String::substr方法代码示例

void URI::ExtractAndSetPath(const Aws::String& uri)
{
    size_t authorityStart = uri.find(SEPARATOR);

    if (authorityStart == Aws::String::npos)
    {
        authorityStart = 0;
    }
    else
    {
        authorityStart += 3;
    }

    size_t pathEnd = uri.find('?');

    if (pathEnd == Aws::String::npos)
    {
        pathEnd = uri.length();
    }

    Aws::String authorityAndPath = uri.substr(authorityStart, pathEnd - authorityStart);

    size_t pathStart = authorityAndPath.find('/');

    if (pathStart != Aws::String::npos)
    {
        SetPath(authorityAndPath.substr(pathStart, pathEnd - pathStart), false);
    }
    else
    {
        SetPath("/");
    }
}

AWSError<CoreErrors> AWSErrorMarshaller::Marshall(const Aws::String& exceptionName, const Aws::String& message) const
{
    auto locationOfPound = exceptionName.find_first_of('#');
    auto locationOfColon = exceptionName.find_first_of(':');
    Aws::String formalExceptionName;

    if (locationOfPound != Aws::String::npos)
    {
        formalExceptionName = exceptionName.substr(locationOfPound + 1);       
    }
    else if (locationOfColon != Aws::String::npos)
    {
        formalExceptionName = exceptionName.substr(0, locationOfColon);       
    }
    else
    {
        formalExceptionName = exceptionName;
    }

    AWSError<CoreErrors> error = FindErrorByName(formalExceptionName.c_str());
    if (error.GetErrorType() != CoreErrors::UNKNOWN)
    {
        AWS_LOG_WARN(logTag, "Encountered AWSError\n%s\n%s:", formalExceptionName.c_str(), message.c_str());
        error.SetExceptionName(formalExceptionName);
        error.SetMessage(message);
        return error;
    }    

    AWS_LOG_WARN(logTag, "Encountered Unknown AWSError\n%s\n%s:", exceptionName.c_str(), message.c_str());

    return AWSError<CoreErrors>(CoreErrors::UNKNOWN, exceptionName, "Unable to parse ExceptionName: " + exceptionName + " Message: " + message, false);
}

        Aws::String Join(char delimiter, const Aws::String& leftSegment, const Aws::String& rightSegment)
        {
            Aws::StringStream ss;

            if (!leftSegment.empty())
            {
                if (leftSegment.back() == delimiter)
                {
                    ss << leftSegment.substr(0, leftSegment.length() - 1);
                }
                else
                {
                    ss << leftSegment;
                }
            }

            ss << delimiter;

            if (!rightSegment.empty())
            {
                if (rightSegment.front() == delimiter)
                {
                    ss << rightSegment.substr(1);
                }
                else
                {
                    ss << rightSegment;
                }
            }

            return ss.str();
        }

QueryStringParameterCollection URI::GetQueryStringParameters(bool decode) const
{
    Aws::String queryString = GetQueryString();

    QueryStringParameterCollection parameterCollection;

    //if we actually have a query string
    if (queryString.size() > 0)
    {
        size_t currentPos = 1, locationOfNextDelimiter = 1;

        //while we have params left to parse
        while (currentPos < queryString.size())
        {
            //find next key/value pair
            locationOfNextDelimiter = queryString.find('&', currentPos);

            Aws::String keyValuePair;

            //if this isn't the last parameter
            if (locationOfNextDelimiter != Aws::String::npos)
            {
                keyValuePair = queryString.substr(currentPos, locationOfNextDelimiter - currentPos);
            }
            //if it is the last parameter
            else
            {
                keyValuePair = queryString.substr(currentPos);
            }

            //split on =
            size_t locationOfEquals = keyValuePair.find('=');
            Aws::String key = keyValuePair.substr(0, locationOfEquals);
            Aws::String value = keyValuePair.substr(locationOfEquals + 1);

            if(decode)
            {
                parameterCollection[StringUtils::URLDecode(key.c_str())] = StringUtils::URLDecode(value.c_str());
            }
            else
            {
                parameterCollection[key] = value;
            }
            currentPos += keyValuePair.size() + 1;
        }
    }

    return parameterCollection;
}

void URI::ExtractAndSetQueryString(const Aws::String& uri)
{
    size_t queryStart = uri.find('?');

    if (queryStart != Aws::String::npos)
    {
        queryString = uri.substr(queryStart);
    }
}

Aws::String ProfileConfigFileAWSCredentialsProvider::GetProfileDirectory()
{
    Aws::String profileFileName = GetCredentialsProfileFilename();
    auto lastSeparator = profileFileName.find_last_of(DIRECTORY_JOIN);
    if (lastSeparator != std::string::npos)
    {
        return profileFileName.substr(0, lastSeparator);
    }
    else
    {
        return "";
    }
}

void URI::ExtractAndSetScheme(const Aws::String& uri)
{
    size_t posOfSeparator = uri.find(SEPARATOR);

    if (posOfSeparator != Aws::String::npos)
    {
        Aws::String schemePortion = uri.substr(0, posOfSeparator);
        SetScheme(SchemeMapper::FromString(schemePortion.c_str()));
    }
    else
    {
        SetScheme(Scheme::HTTP);
    }
}

void URI::ExtractAndSetAuthority(const Aws::String& uri)
{
    size_t authorityStart = uri.find(SEPARATOR);

    if (authorityStart == Aws::String::npos)
    {
        authorityStart = 0;
    }
    else
    {
        authorityStart += 3;
    }

    size_t posOfEndOfAuthorityPort = uri.find(':', authorityStart);
    size_t posOfEndOfAuthoritySlash = uri.find('/', authorityStart);
    size_t posOfEndOfAuthorityQuery = uri.find('?', authorityStart);
    size_t posEndOfAuthority = std::min({posOfEndOfAuthorityPort, posOfEndOfAuthoritySlash, posOfEndOfAuthorityQuery});
    if (posEndOfAuthority == Aws::String::npos)
    {
        posEndOfAuthority = uri.length();
    }

    SetAuthority(uri.substr(authorityStart, posEndOfAuthority - authorityStart));
}