private void VisitBinaryCriterionExpression(BinaryExpression expr)
{
ComparePropToValue comparePropToValue = null;
ComparePropToProp comparePropToProp = null;
CompareValueToCriteria compareValueToCriteria = null;
ComparePropToCriteria comparePropToCriteria = null;
switch (expr.NodeType)
{
case ExpressionType.Equal:
comparePropToValue = (n, v) => (v != null) ? Restrictions.Eq(n, v) : Restrictions.IsNull(n);
comparePropToProp = Restrictions.EqProperty;
compareValueToCriteria = Subqueries.Eq;
comparePropToCriteria = Subqueries.PropertyEq;
break;
case ExpressionType.GreaterThan:
comparePropToValue = Restrictions.Gt;
comparePropToProp = Restrictions.GtProperty;
compareValueToCriteria = Subqueries.Gt;
comparePropToCriteria = Subqueries.PropertyGt;
break;
case ExpressionType.GreaterThanOrEqual:
comparePropToValue = Restrictions.Ge;
comparePropToProp = Restrictions.GeProperty;
compareValueToCriteria = Subqueries.Ge;
comparePropToCriteria = Subqueries.PropertyGe;
break;
case ExpressionType.LessThan:
comparePropToValue = Restrictions.Lt;
comparePropToProp = Restrictions.LtProperty;
compareValueToCriteria = Subqueries.Lt;
comparePropToCriteria = Subqueries.PropertyLt;
break;
case ExpressionType.LessThanOrEqual:
comparePropToValue = Restrictions.Le;
comparePropToProp = Restrictions.LeProperty;
compareValueToCriteria = Subqueries.Le;
comparePropToCriteria = Subqueries.PropertyLe;
break;
case ExpressionType.NotEqual:
comparePropToValue = (n, v) => (v != null) ? Restrictions.Not(Restrictions.Eq(n, v)) : Restrictions.IsNotNull(n);
comparePropToProp = Restrictions.NotEqProperty;
compareValueToCriteria = Subqueries.Ne;
comparePropToCriteria = Subqueries.PropertyNe;
break;
}
CurrentCriterions.Add(
BinaryCriterionVisitor.GetBinaryCriteria(rootCriteria, session,
expr, comparePropToValue, comparePropToProp,
compareValueToCriteria, comparePropToCriteria));
}
public static ICriterion GetBinaryCriteria(
ICriteria rootCriteria,
ISession session,
BinaryExpression expr,
ComparePropToValue comparePropToValue,
ComparePropToProp comparePropToProp,
CompareValueToCriteria compareValueToCriteria,
ComparePropToCriteria comparePropToCriteria)
{
var left = new BinaryCriterionVisitor(rootCriteria, session);
var right = new BinaryCriterionVisitor(rootCriteria, session);
left.Visit(expr.Left);
right.Visit(expr.Right);
//the query should have been preprocessed so that
//only the following combinations are possible:
// LEFT RIGHT
// ========================
// property value
// property property
// property criteria
// value criteria
// criteria criteria <== not supported yet
switch (left.Type)
{
case BinaryCriterionType.Property:
switch (right.Type)
{
case BinaryCriterionType.Value:
object val = right.Value;
if (left.ConvertTo != null)
{
val = LinqUtil.ChangeType(val, left.ConvertTo);
}
return(comparePropToValue(left.Name, val));
case BinaryCriterionType.Property:
return(comparePropToProp(left.Name, right.Name));
case BinaryCriterionType.Criteria:
return(comparePropToCriteria(left.Name, right.Criteria));
}
break;
case BinaryCriterionType.Value:
return(compareValueToCriteria(left.Value, right.Criteria));
}
throw new NotSupportedException("Could not understand: " + expr);
}
public static ICriterion GetBinaryCriteria(
ICriteria rootCriteria,
ISession session,
BinaryExpression expr,
ComparePropToValue comparePropToValue,
ComparePropToProp comparePropToProp,
CompareValueToCriteria compareValueToCriteria,
ComparePropToCriteria comparePropToCriteria)
{
var left = new BinaryCriterionVisitor(rootCriteria, session);
var right = new BinaryCriterionVisitor(rootCriteria, session);
left.Visit(expr.Left);
right.Visit(expr.Right);
//the query should have been preprocessed so that
//only the following combinations are possible:
// LEFT RIGHT
// ========================
// property value
// property property
// property criteria
// value criteria
// criteria criteria <== not supported yet
switch (left.Type)
{
case BinaryCriterionType.Property:
switch (right.Type)
{
case BinaryCriterionType.Value:
object val = right.Value;
if (left.ConvertTo != null)
val = LinqUtil.ChangeType(val, left.ConvertTo);
return comparePropToValue(left.Name, val);
case BinaryCriterionType.Property:
return comparePropToProp(left.Name, right.Name);
case BinaryCriterionType.Criteria:
return comparePropToCriteria(left.Name, right.Criteria);
}
break;
case BinaryCriterionType.Value:
return compareValueToCriteria(left.Value, right.Criteria);
}
throw new NotSupportedException("Could not understand: " + expr);
}
