Example 10: Get Capabilities

Example: Examples of getting various Twain device capabilities.  Illustrated are the gamma values (double values), transfer mechanisms ( long values ), and author (string value).

#include "cdtwain.h"

#include <iostream>

#include <string>

using namespace DTWAIN;

using namespace std;

// Function to display all values of that have been retrieved from the Source that have

// been stored in "ArrayType".  Note that the arrays are actually STL vectors, so any

// std::vector operations will work.

template <typename ArrayType>

void DisplayAllCapValues(const std::string& CapName, const std::string& CapOp, const ArrayType& AT)

{

   cout << "Capability values for " << CapName << endl

          << "Cap operation = " << CapOp << endl;

   ArrayType::const_iterator it = AT.begin( );

   ArrayType::const_iterator it2 = AT.end( );

   if ( it == it2 )

       cout << "No values are available..."  << endl;

   else

   {

       while ( it != it2 )

       {

           cout << *it << endl;

           ++it;

       }

       cout << endl;

   }

}

int main( )

{

  LONG CapOpType[] = { DTWAIN_CAPGET, DTWAIN_CAPGETCURRENT, DTWAIN_CAPGETDEFAULT };

  char *CapOpName[] = {"Get Values", "Get Current Values", "Get Default Values"};

  // Initialize DTWAIN - return if initialization does not work

  DTwainInterface TI;

  if ( !TI.IsValid( ) )

      return 0;

  // Select a Source

  DTwainSource Source = DTwainSource::Select( );

  if ( !Source.IsValid( ) )

     return 0;

  // Get the Gamma value of the Source

  DTwainDoubleArray GammaValue;

  int i;

  for ( i = 0; i < 3; ++i )

  {  

      Source.GetCapValues( DTWAIN_CV_ICAPGAMMA, GammaValue, CapOpType[ i ] );

      DisplayAllCapValues( "DTWAIN_CV_ICAPGAMMA", CapOpName[i], GammaValue );

  }

  // Get the transfer mechanism's available for the source

  DTwainLongArray XferMechValues;

  for ( i = 0; i < 3; ++i )

  {  

      Source.GetCapValues( DTWAIN_CV_ICAPXFERMECH, XferMechValues, CapOpType[ i ] );

      DisplayAllCapValues( "DTWAIN_CV_ICAPXFERMECH", CapOpName[i], XferMechValues );

  }

  // Get the author values available for the source

  DTwainStringArray Author;

  for ( i = 0; i < 3; ++i )

  {  

      Source.GetCapValues( DTWAIN_CV_CAPAUTHOR, Author, CapOpType[ i ] );

      DisplayAllCapValues( "DTWAIN_CV_CAPAUTHOR", CapOpName[i], Author );

  }

}