public static EntityCollection FetchRandom ( )
{
EntityCollection result =
Context.Current.Session[ "CachedRandomQuestions" ]
as EntityCollection;
if ( result == null )
{
result = new EntityCollection ( );
EntityCollection entityCollection = new EntityCollection ( );
foreach ( Entity entity in FetchAll ( ) )
{
entityCollection.Add ( entity );
}
int numberOfEntities = Configuration.NumberOfQuestionsToDisplay;
Random random = new Random ( );
for ( int index = 0; index < numberOfEntities; ++index )
{
int randomIndex = random.Next ( numberOfEntities );
result.Add ( entityCollection[ randomIndex ] );
entityCollection.RemoveAt ( randomIndex );
}
Context.Current.Session[ "CachedRandomQuestions" ] = result;
}
return result;
}
public static EntityCollection FetchAll ( )
{
EntityCollection result =
Context.Current.Session[ "CachedQuestions" ]
as EntityCollection;
if ( result == null )
{
result = new EntityCollection ( );
string[] dataRows =
DataStore.Fetch ( ).Split ( new char[] { '\n', '\r' } );
foreach ( string dataRow in dataRows )
{
if ( !string.IsNullOrEmpty ( dataRow ) )
{
string[] dataColumns =
dataRow.Substring (
( dataRow.IndexOf ( ',' ) + 1 ) ).Split ( ',' );
Question question = new Question ( );
try
{
question.Answers = new EntityCollection ( );
question.Id = Guid.NewGuid ( ).ToString ( "N" );
question.Value =
dataRow.Substring ( 0, ( dataRow.IndexOf ( ',' ) ) );
foreach ( string dataColumn in dataColumns )
{
if ( !string.IsNullOrEmpty ( dataColumn ) )
{
Answer answer = new Answer ( );
answer.Id = Guid.NewGuid ( ).ToString ( "N" );
answer.Value =
dataColumn.Replace ( "*", string.Empty );
if ( dataColumn.IndexOf ( '*' ) > -1 )
{
question.CorrectAnswerId = answer.Id;
}
question.Answers.Add ( answer );
}
}
}
catch
{
throw new Exception ( "The application could not retrieve the questions." );
}
result.Add ( question );
}
}
Context.Current.Session[ "CachedQuestions" ] = result;
}
return result;
}
