Need help with formulating LINQ query
I'm building a word anagram program that uses a database which contains one simple t开发者_JAVA百科able:
Words
---------------------
varchar(15) alphagram
varchar(15) anagram
(other fields omitted for brevity)
An alphagram is the letters of a word arranged in alphabetical order. For example, the alphagram for OVERFLOW would be EFLOORVW. Every Alphagram in my database has one or more Anagrams. Here's a sample data dump of my table:
Alphagram Anagram
EINORST NORITES
EINORST OESTRIN
EINORST ORIENTS
EINORST STONIER
ADEINRT ANTIRED
ADEINRT DETRAIN
ADEINRT TRAINED
I'm trying to build a LINQ query that would return a list of Alphagrams along with their associated Anagrams. Is this possible?
UPDATE: Here's my solution based on the suggestions below! Thanks all!
using (LexiconEntities ctx = new LexiconEntities())
{
var words = ctx.words;
var query =
from word in words
where word.alphagram == "AEINRST"
group word by word.alphagram into alphagramGroup
select new { Alphagram = alphagramGroup.Key, Anagrams = alphagramGroup };
foreach (var alphagramGroup in query)
{
Console.WriteLine("Alphagram: {0}", alphagramGroup.Alphagram);
foreach (var anagram in alphagramGroup.Anagrams)
{
Console.WriteLine("Anagram: {0}", anagram.word1);
}
}
}
var list = anagrams.Select(
a => new {
Alphagram = a.ToCharArray().OrderBy(s => s).ToString(),
Anagram = a
}).toList();
A totally new answer...
You seem to need a groupby query look at How to: Group Data (Entity Framework).
this should accomplish what you want...
I did a testy with LINQ and this works...
var words = new List<Word>()
{
new ConsoleApplication1.Word("EINORST", "NORITES"),
new ConsoleApplication1.Word("EINORST", "OESTRIN"),
new ConsoleApplication1.Word("EINORST", "STONIER"),
new ConsoleApplication1.Word("ADEINRT", "ANTIRED"),
new ConsoleApplication1.Word("ADEINRT", "DETRAIN"),
new ConsoleApplication1.Word("ADEINRT", "TRAINED")
};
var q = words.GroupBy(w => w.Alphagram).Select(w => new { Alphagram = w.Key, Anagrams = w.Select(p => p.Anagram).ToList() }).ToList();
foreach (var item in q)
{
Console.WriteLine("Alphagram : {0}, Anagrams = {1}", item.Alphagram, String.Join(",", item.Anagrams));
}
var words = new List<Words>()
{
new Words("EINORST", "NORITES"),
new Words("EINORST", "OESTRIN"),
new Words("EINORST", "STONIER"),
new Words("ADEINRT", "ANTIRED"),
new Words("ADEINRT", "DETRAIN"),
new Words("ADEINRT", "TRAINED")
};
var result = words.GroupBy(w => w.Alphagram, w => w.Anagram)
.Select(w => new {
Alphagram = w.Key,
Anagrams = w.Where(p => w.Key.ToCharArray().SequenceEqualUnOrdered(p.ToCharArray())).ToList()
}
)
.ToList();
public static bool SequenceEqualUnOrdered<T>(this IEnumerable<T> first, IEnumerable<T> second)
{
return new HashSet<T>(first).SetEquals(second);
}
Is it what you are looking for? It is LINQ to Objects. You may want to use LINQ-to-SQL or LINQ-to-Entites to fetch your records into your objects and then use the above-mentioned LINQ-to-Objects query over the already-fetched object collection.
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