protected override FilterExpression Transform(FilterCallExpression lx)
{
if (!Operators.WildcardComparators.Contains(lx.OperatorName) || lx.Operands.Length != 2)
{
return(base.Transform(lx));
}
var lhsIs = FilterExpressionWildcardSearch.FindElementAtWildcard(lx.Operands[0]);
var rhsIs = FilterExpressionWildcardSearch.FindElementAtWildcard(lx.Operands[1]);
if (lhsIs != null && rhsIs != null || lhsIs == null && rhsIs == null)
{
return(base.Transform(lx)); // N/A, or invalid
}
var wcpath = lhsIs != null ? lx.Operands[0] : lx.Operands[1];
var comparand = lhsIs != null ? lx.Operands[1] : lx.Operands[0];
var elmat = lhsIs ?? rhsIs;
var parm = new FilterParameterExpression("p" + _nextParameter++);
var nestedComparand = FilterExpressionNodeReplacer.Replace(wcpath, elmat, parm);
var coll = elmat.Operands[0];
var wc = ((FilterWildcardExpression)elmat.Operands[1]).Wildcard;
var comparisonArgs = lhsIs != null ? new[] { nestedComparand, comparand } : new[] { comparand, nestedComparand };
var body = new FilterCallExpression(lx.OperatorName, comparisonArgs);
var lambda = new FilterLambdaExpression(new[] { parm }, body);
var op = Operators.ToRuntimeWildcardOperator(wc);
var call = new FilterCallExpression(op, new[] { coll, lambda });
return(Transform(call));
}
public static FilterCallExpression FindElementAtWildcard(FilterExpression fx)
{
var search = new FilterExpressionWildcardSearch();
return(search.Transform(fx));
}