private static SimpleExpression CompileExpression <T>(DonationSearchCriteria donationCriteria, T amount, dynamic column)
where T : IComparable <T>
{
switch (donationCriteria.SearchOperator)
{
case SearchOperator.EqualTo:
return(column == amount);
case SearchOperator.NotEqualTo:
return(column != amount);
case SearchOperator.GreaterThan:
return(column > amount);
case SearchOperator.GreaterThanOrEqualTo:
return(column >= amount);
case SearchOperator.LessThan:
return(column < amount);
case SearchOperator.LessThanOrEqualTo:
return(column <= amount);
default:
throw new InvalidOperationException("Operator not valid with decimal value.");
}
}
private SimpleExpression CompileTotalDonationCriteria(DonationSearchCriteria donationCriteria)
{
var column = db.Members.Donations.Amount.Sum();
decimal amount;
if (!decimal.TryParse(donationCriteria.Value, out amount))
{
throw new InvalidOperationException("Cannot convert value to decimal.");
}
return(CompileExpression(donationCriteria, amount, column));
}
private SimpleExpression CompileLastDonationDate(DonationSearchCriteria donationCriteria)
{
var column = db.Members.Donations.Date.Max();
DateTime date;
if (!DateTime.TryParse(donationCriteria.Value, out date))
{
throw new InvalidOperationException("Cannot convert value to date.");
}
return(CompileExpression(donationCriteria, date, column));
}
