c++ - How can I read a file line content using line number -

i have following code snippet working fine:

 ifstream ndsconfig( "nds.config" ) ;         string szconfigval ;         while( getline( ndsconfig, szconfigval ) )         {             //code         } 

but problem need update check box state comparing line values. code similar following:

 ifstream ndsconfig( "nds.config" ) ;         string szconfigval ;         while( getline( ndsconfig, szconfigval ) )         {             if(szconfigval == "autostart = 1")             {                       //set check box true             }             else if(szconfigval == "autostart = 0")             {                       //set check box false             }              if(szconfigval == "autloghistory = 1")             {                       //set check box true             }             else if(szconfigval == "autloghistory = 0")             {                       //set check box false             }              if(szconfigval == "autoscan = 1")             {                       //set check box true             }             else if(szconfigval == "autoscan = 0")             {                       //set check box false             }              if(szconfigval == "automount = 1")             {                       //set check box true             }             else if(szconfigval == "automount = 0")             {                       //set check box false             }              if(szconfigval == "autoopen = 1")             {                       //set check box true             }             else if(szconfigval == "autoopen = 0")             {                       //set check box false             }              if(szconfigval == "lastconnectedsvr = 1")             {                       //set check box true             }             else if(szconfigval == "lastconnectedsvr = 0")             {                       //set check box false             }         } 

if going use while loop state on riden , last in loop value or state updated. there other way out. need set check box values after reading config file . config file looks below:

autostart = 0
autloghistory = 1
autoscan = 1
automount = 0
autoopen = 0
lastconnectedsvr = 1

though can have single if , else else if need better way.

alternatively, use boost::program_options, designed require!

edit: little more detail, program_options has method parse config file, such yours, , configure program_options, can pass in variable store value config file in. have @ simple example, become abundantly clear...

other option store keys in map, default value of 0, , parse through file, set key value read file...

edit:

using program options (this untested code, please try refer documentation , fix needed!)

int autostart; int autloghistory; int autoscan; int automount; int autoopen; int lastconnectedsvr;  po::options_description desc("allowed options"); desc.add_options()     ("help", "produce message")     ("autostart", po::value<int>(&autostart)->default_value(0),"autostart")     ("autloghistory", po::value<int>(&autloghistory)->default_value(0),"autloghistory")     ("autoscan", po::value<int>(&autoscan)->default_value(0),"autoscan")     ("automount", po::value<int>(&automount)->default_value(0),"automount")     ("autoopen", po::value<int>(&autoopen)->default_value(0),"autoopen")     ("lastconnectedsvr", po::value<int>(&lastconnectedsvr)->default_value(0),"lastconnectedsvr") ;  std::ifstream config("nds.config");  po::parse_command_line(config, desc, true); 

when lot runs, various integers have values file (or defaulted 0).

the neat thing approach can have different types in config files, , long formatted ini files, work.

the other approach using std::map, @moo-juice has added working code...