c++ - How to solve "boost::bad_any_cast: failed conversion using boost::any_cast" when using boost program options? -

  // Use the Boost Program option to read command line and configured file data #include & lt; Boost / program_options.hpp and gt; using namespace std; Using Namespace Boost; Name space po = boost :: program_options; Int main (int argc, char * argv []) {po :: options_description config ("configuration"); Config.add_options () ("IPAddress, i", "IP Address") ("Port, P", "Port"); Po :: variables_map vm; Po :: store (po :: parse_command_line (argc, argv, config), vm); Po :: Notify (VM); Cout & lt; & Lt; "Value \ n"; String Address = (VM ["IP Address"]. & Lt; std :: string & gt; ()). C_str (); String port = (VM ["port"]. As & lt; std: string & gt; ()). C_str (); Cout & lt; & Lt; (Vm ["IPAddress"]. & Lt; string & gt; ()). C_str (); Cout & lt; & Lt; "" & Lt; & Lt; (VM ["Port"] & lt;; string & gt; ()). C_str (); Return 0; }   
 Is the input value somehow unreliable?  
 Here is the GDB output, it seems that the problem can be solved:  
 
 Finish Boost :: exception_detail :: clone_impl  
 
 '(): Boost :: bad_any_cast: boost :: any_cast   
  programmable signals SIGABRT, abort 0x0000003afd835935 in raise () to /lib64/libc.so.6    
  string address = (vm ["IPAddress"]. As  ()) c_str () .;   
 That error occurs; I have tried std :: string and string with the same result.  
  testboostpo -i 192.168.1.10 -p 5000   
 is the command line. <
 
  config.add_options () ("IPAddress, i", po :: value & lt; std :: string & gt; (), "IP address") ("Port, P ", Po :: value  ()," port ");   
 But the error still occurred.  
 Can this be a real bug?   
 
 
 You  boost :: bad_any_cast  to  po :: variables_map < See exceptions removed from / code> because the two  const char *  does not specify a  po :: value_semantic  type of logic overload, so it should be returned to any  std :: String will not be converted to . If you want to convert the value to  std :: string , and it is necessary for your application, then use  required ()  value.  
  #include & lt; Boost / program_options.hpp & gt; Name space po = boost :: program_options; Int main (int argc, char * argv []) {po :: options_description config ("configuration"); Config.add_options () ("IPAddress, i", po :: value & lt; std :: string & gt; () - & gt; Required (), "IP address") ("Port, P", PO: : Value & lt; std:: string & gt; () - & gt; required (), "port"); Try {po :: variables_map vm; Po :: store (po :: parse_command_line (argc, argv, config), vm); Po :: Notify (VM); Std :: cout & lt; & Lt; "Value" & lt; & Lt; Std :: endl; Const std :: string address = vm ["IPAddress"]. & Lt; Std :: string & gt; (); Const std :: string port = vm ["port"]. As & lt; Std :: string & gt; (); Std :: cout & lt; & Lt; "Address:" & lt; & Lt; Address & lt; & Lt; Std :: endl; Std :: cout & lt; & Lt; "Port:" & lt; & Lt; Harbor & lt; & Lt; Std :: endl; } Hold (const std :: exception & e) {std :: cerr & lt; & Lt; E.what () & lt; & Lt; Std :: endl; Return 1; } Return 0; }   
 Note the added block block since parsing (and as you've noted) Leave Exception Here is a sample session:  
  Samm $ ./a.out Option '- IPADress' is required, but SAMM $ / A.out is unavailable - IPRAR 127.0.0.1 option requires 'port -' but SAM $ is missing. / A.out - IPadder 127.0.0.1 - Port 5000 Price Address: 127.0.0.1 Port: 5000 SAM $   
 Here is the courtesy behavior of the compile link RUIN (Koloiru), the same behavior Showing