Lambda Iterational Filtering

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C#

C#4.0

lambda

Dear all,

I am using lambda expressions in C# in order to filter within a database entity. The table I am accessing is using a hierarchical tree structure and a particular entity can have infinite levels of children, which can be accessed by .Children, for example:

string name = entity.Children.First().Children.First().Children.First().Name;

I am trying to find a root node that contains a particular value for a given child. So for instance, the method will take a name parameter which can be "Level1.Level2.Name" and value parameter which can be "Test".

So in this case, I need to check for a node which has a Child named Level1, and this child must in turn contain a Child named Level2 which has another Child called Name and has the value of Test.


What I tried so far is something like this:

var predicate = PredicateBuilder.True<Attribute>();
predicate = predicate.And(a => a.ParentId == 5).Expand();

// segments is the input name split into a string[] by the '.' character
for (int x = 0; x < segments.Length; x++)
{
    string tmpSegment = segments[x];

    predicate = predicate.And(e => e.Children.Any(c => c.Name.Equals(tmpSegment, StringComparison.OrdinalIgnoreCase))).Expand();
}

query = query.Where(predicate);

// Execute query and retrieve results...

The problem is that this query is all being evaluated on the base node. I need to repeat the Name checking predicate on its Children, and the Children's Children.

If any part of my question is unclear do not hesitate to ask.

Thanks!


Edit #1:

LinqKit is already being used in other parts of this project. So if you have a suggestion that uses LinqKit, it is also acceptable :)