void IQueryVisitor.Visit(FilteringDescriptor filter)
{
// The member you want to evaluate (x => x.FirstName)
Expression member = LinqExpressionHelper.GetMemberChainExpression(_param, filter.Field);
// The value you want to evaluate
Expression constant = Expression.Constant(filter.Criterion);
if (filter.IgnoreCase && filter.Criterion is string)
{
member = Expression.Call(Expression.Coalesce(member, LinqProviderStatic.EmptyStr), LinqProviderStatic.ToUpper);
constant = Expression.Constant(string.IsNullOrEmpty((string)filter.Criterion) ? string.Empty : (string)filter.Criterion);
constant = Expression.Call(constant, LinqProviderStatic.ToUpper);
}
// Determine how we want to apply the expression
switch (filter.Predicate)
{
case CriterionPredicate.Eq:
case CriterionPredicate.Null:
_expression = Expression.Equal(member, constant);
break;
case CriterionPredicate.Neq:
case CriterionPredicate.NotNull:
_expression = Expression.NotEqual(member, constant);
break;
case CriterionPredicate.Gt:
_expression = Expression.GreaterThan(member, constant);
break;
case CriterionPredicate.GtEq:
_expression = Expression.GreaterThanOrEqual(member, constant);
break;
case CriterionPredicate.Lt:
_expression = Expression.LessThan(member, constant);
break;
case CriterionPredicate.LtEq:
_expression = Expression.LessThanOrEqual(member, constant);
break;
case CriterionPredicate.Contains:
//return Expression.AndAlso(Expression.NotEqual(member, Expression.Constant(null)),
//Expression.Call(member, PaggedLinqBaseStatics.ContainsMethod, constant));
_expression = Expression.Call(Expression.Coalesce(member, LinqProviderStatic.EmptyStr), LinqProviderStatic.ContainsMethod, constant);
break;
case CriterionPredicate.StartsWith:
_expression = Expression.Call(Expression.Coalesce(member, LinqProviderStatic.EmptyStr), LinqProviderStatic.StartsWithMethod, constant);
break;
case CriterionPredicate.EndsWith:
_expression = Expression.Call(Expression.Coalesce(member, LinqProviderStatic.EmptyStr), LinqProviderStatic.EndsWithMethod, constant);
break;
}
}
public QueryPaggedBase <TItem, TResult> AddFiltering(Expression <Func <TItem, object> > memberSelector, object criterion, CriterionPredicate predicate = CriterionPredicate.Eq, bool ignoreCase = false)
{
if (_filtering == null)
{
_filtering = new FilteringCollection();
}
_filtering.Add(FilteringDescriptor.Get(memberSelector, criterion, predicate, ignoreCase));
return(this);
}
void IQueryVisitor.Visit(FilteringDescriptor fd)
{
Tuple <string, bool> p = GetSqlPredicate(fd.Predicate);
if (p.Item2)
{
_bld.AppendFormat("[{0}] {1} {2}", fd.Field, p.Item1, Quote(fd.Criterion, fd.Predicate));
}
else
{
_bld.AppendFormat("[{0}] {1}", fd.Field, p.Item1);
}
}
public void TestLinqWIthConversion()
{
var f1 = new FilteringDescriptor()
{
Field = "f1", Predicate = CriterionPredicate.Gt, Criterion = "sss"
};
var f2 = new FilteringDescriptor()
{
Field = "f1", Predicate = CriterionPredicate.Gt, Criterion = "sss"
};
var f3 = new FilteringDescriptor()
{
Predicate = CriterionPredicate.Gt, Criterion = "sss"
};
var f4 = new FilteringDescriptor()
{
Field = "f1", Predicate = CriterionPredicate.Gt
};
var f5 = new FilteringDescriptor()
{
Field = "f1", Predicate = CriterionPredicate.Lt, Criterion = "sss"
};
var f6 = new FilteringDescriptor()
{
Field = "f2", Predicate = CriterionPredicate.Gt, Criterion = "sss"
};
var f7 = new FilteringDescriptor()
{
Field = "f1", Predicate = CriterionPredicate.Gt, Criterion = "sss2"
};
Assert.IsTrue(f1 == f2);
Assert.IsFalse(f1 == f3);
Assert.IsFalse(f1 == f4);
Assert.IsFalse(f1 == f5);
Assert.IsFalse(f1 == f6);
Assert.IsFalse(f1 == f7);
Assert.IsFalse(f1 < f2);
Assert.IsFalse(f1 < f3);
Assert.IsFalse(f1 < f4);
Assert.IsFalse(f1 < f5);
Assert.IsTrue(f1 < f6);
Assert.IsTrue(f1 < f7);
}
void IQueryVisitor.Visit(FilteringDescriptor fd)
{
Tuple<string, bool> p = GetSqlPredicate(fd.Predicate);
if (p.Item2)
_bld.AppendFormat("[{0}] {1} {2}", fd.Field, p.Item1, Quote(fd.Criterion, fd.Predicate));
else
_bld.AppendFormat("[{0}] {1}", fd.Field, p.Item1);
}
