private int Eval(BinaryNode expr, DataRow row, DataRowVersion version)
{
if (expr.op == Operators.And)
{
int lResult = Eval((BinaryNode)expr.left, row, version);
if (lResult != 0)
{
return(lResult);
}
int rResult = Eval((BinaryNode)expr.right, row, version);
if (rResult != 0)
{
return(rResult);
}
return(0);
}
long c = 0;
object vLeft = expr.left.Eval(row, version);
if (expr.op != Operators.Is && expr.op != Operators.IsNot)
{
object vRight = expr.right.Eval(row, version);
bool isLConst = (expr.left is ConstNode);
bool isRConst = (expr.right is ConstNode);
if (vLeft == DBNull.Value)
{
return(-1);
}
if (vRight == DBNull.Value)
{
return(1);
}
if (vLeft.GetType() == typeof(char))
{
vRight = Convert.ToChar(vRight);
}
Type result = expr.ResultType(vLeft.GetType(), vRight.GetType(), isLConst, isRConst, expr.op);
if (result == null)
{
expr.SetTypeMismatchError(expr.op, vLeft.GetType(), vRight.GetType());
}
c = expr.Compare(vLeft, vRight, result, expr.op);
}
switch (expr.op)
{
case Operators.EqualTo: c = (c == 0 ? 0 : c < 0 ? -1 : 1); break;
case Operators.GreaterThen: c = (c > 0 ? 0 : -1); break;
case Operators.LessThen: c = (c < 0 ? 0 : 1); break;
case Operators.GreaterOrEqual: c = (c >= 0 ? 0 : -1); break;
case Operators.LessOrEqual: c = (c <= 0 ? 0 : 1); break;
case Operators.Is: c = (vLeft == DBNull.Value ? 0 : -1); break;
case Operators.IsNot: c = (vLeft != DBNull.Value ? 0 : 1); break;
default: Debug.Assert(true, "Unsupported Binary Search Operator!"); break;
}
return((int)c);
}
