Thread: token text problem

Code:

#include <vector>
#include <map>
#include <string>
#include <iostream>
#include <fstream>
#include <sstream>

using namespace std;

vector<string> split( const string & s );

class csvreader {
public:
    csvreader(const char * fname );
    bool write_data( const char * fname, vector<string> & outputorder );
protected:
    void make_ordermap (vector<string> & vs );
    void read_data( istream & in );
    vector<vector<string> >  data;
    map<string, int>         order;
};


vector<string> split( const string & s ) {
    stringstream str( s );
    vector<string> sv;
    string item;
    while ( getline( str, item, ';' ) )
       sv.push_back( item );       
    return sv;
}


csvreader::csvreader( const char * fname ) {
    ifstream in( fname );
    if ( !in )
        return;
    string header;
    getline( in, header );
    vector<string> hv = split( header );
    make_ordermap( hv );
    read_data( in );
}

void csvreader::read_data( istream & in ) {
    string line;
    while( getline( in, line ) )
        data.push_back(split( line ));
}

void csvreader::make_ordermap(vector<string> & vs ) {
    int index = 0;
    for ( vector<string>::iterator i = vs.begin(); i != vs.end(); ++i, ++index ) 
        order.insert( make_pair( *i, index ));
}

bool csvreader::write_data( const char * fname, vector<string> & outputorder ) {
    
    ofstream out( fname );
    if ( ! out ) 
        return false;
    
    vector<string>::size_type len = outputorder.size();
    vector<string>::size_type cou = 0;
    
    // create a vector holding the index order for output
    vector<int> ov;
    
    for ( vector<string>::iterator i = outputorder.begin(); i != outputorder.end(); ++i ) {
        map<string, int>::iterator fi = order.find( *i );
        if ( fi != order.end() )
            ov.push_back((*fi).second);        
        else 
            // field is not available
            return false; 
    }
                    
    // write the header 
    for ( vector<string>::iterator i = outputorder.begin(); i != outputorder.end(); ++i, ++cou ) {
        out << *i;
        if ( cou < len-1 )
            out << ";";
    }
    out << endl;
   
    // write the data
    cou = 0;
    for ( vector<vector<string> >::iterator i = data.begin(); i != data.end(); ++ i ) {
        vector<string> & dta = *i;
        vector<string>::size_type olen = outputorder.size();
        
        for ( vector<string>::size_type ocou = 0; ocou < olen; ++ocou ) {
            int idx = ov[ ocou ];
            if ( idx >= olen )
                return false;   // not enough data
            out << dta[idx];
            if ( ocou < olen -1 )
                out << ";";
        }
        out << endl;
    }
    return true;
}

int main() {
    csvreader reader("data.csv");  
    /*ID;Data;Tag;Date */
    vector<string> output_order;
    output_order.push_back("Date");
    output_order.push_back("Tag");
    output_order.push_back("Data");
    output_order.push_back("ID");
    if ( ! reader.write_data("new.csv", output_order ) )
        cout << "there is something wrong with your data" << endl;
    return 0;
}
/*
the input file

ID;Data;Tag;Date
234;15681;345919;91234
156;1924;;134
156;1824;;234

the output file

Date;Tag;Data;ID;
91234;345919;15681;234
134;;1924;156
234;;1824;156
*/

I'm too lazy to explain with words.
Kurt

And yet a full answer that wont help the op more than a broken finger.....good one