Question

I have a string array in this format (each line is a slot in the array):

IT1
PID
Ref
Ref
REF
IT1
PID
REF
IT1
PID
Ref
REF
…

I want to extract each IT1 through the last REF into a new array using LINQ. The new result would be an IEnumerable<IEnumerable<string>>.

Using the above string slot array example, the new IEnumerable collection should have 3 IEnumerable<string> in it.

For example:

class 1
IT1
PID
Ref
Ref
REF
end class 1

class 2
IT1
PID
REF
end class 2

class 3
IT1
PID
Ref
REF
end class 3
…

Notice some sections of the array have 1 REF, some 2 REF and some 3 REF.

How can I use LINQ to extract each section from IT1 through the last REF into a new collection of IEnumerable<IEnumerable<string>>?

Psudo code…

var result = arrayData.Select(s => s.StartsWith("IT1")
.GroupBy(...)
.Select(result => new {IT1 through last ref goes here})
.ToArray();

Thanks all for the help!

Answer 1

You can partition the array using GroupBy and some temporary state like this:

var counter = 0;
var arrays = input.GroupBy(s => counter += s == "IT1" ? 1 : 0)
                  .Select(g => g.ToArray())
                  .ToArray();

This will give you an array of arrays; each sub-array will start with an "IT1" element and end with whatever your input had before the next "IT1". If your data is valid, that will be a "REF". If the data is invalid, you need to specify what should happen in this case.

I ‘m not so sure how you expect these arrays to be converted into anonymous objects though. Anonymous objects might have an unknown type name, but they are still very strongly typed: you cannot dynamically decide the amount, names, and types of their members.