break long string into multiple c++

Question

I have a string that is received from third party. This string is actually the text from a text file and it may contain UNIX LF or Windows CRLF for line termination. How can I break this into multiple strings ignoring blank lines? I was planning to do the following, but am not sure if there is a better way. All I need to do is read line by line. Vector here is just a convenience and I can avoid it. * Unfortunately I donot have access to the actual file. I only receive the string object *

string textLine;
vector<string> tokens;

size_t pos = 0;
while( true ) {
    size_t nextPos = textLine.find( pos, '\n\r' );
    if( nextPos == textLine.npos )
        break;
    tokens.push_back( string( textLine.substr( pos, nextPos - pos ) ) );
    pos = nextPos + 1;
}

Answer 1

You could use std::getline as you're reading from the file instead of reading the whole thing into a string. That will break things up line by line by default. You can simply not push_back any string that comes up empty.

string line;
vector<string> tokens;

while (getline(file, line))
{
    if (!line.empty()) tokens.push_back(line);
}

UPDATE:

If you don't have access to the file, you can use the same code by initializing a stringstream with the whole text. std::getline works on all stream types, not just files.