I have used the "select" keyword and extension method to return an IEnumerable<T>
with LINQ, but I have a need to return a generic Dictionary<T1, T2>
and can't figure it out. The example I learned this from used something in a form similar to the following:
IEnumerable<T> coll = from x in y
select new SomeClass{ prop1 = value1, prop2 = value2 };
I've also done the same thing with extension methods. I assumed that since the items in a Dictionary<T1, T2>
can be iterated as KeyValuePair<T1, T2>
that I could just replace "SomeClass" in the above example with "new KeyValuePair<T1, T2> { ...
", but that didn't work (Key and Value were marked as readonly, so I could not compile this code).
Is this possible, or do I need to do this in multiple steps?
Thanks.
var dictionary = (from x in y
select new SomeClass
{
prop1 = value1,
prop2 = value2
}
).ToDictionary(item => item.prop1);
That's assuming that SomeClass.prop1
is the desired Key
for the dictionary.
A more explicit option is to project collection to an IEnumerable of KeyValuePair
and then convert it to a Dictionary.
Dictionary<int, string> dictionary = objects
.Select(x=> new KeyValuePair<int, string>(x.Id, x.Name))
.ToDictionary(x=>x.Key, x=>x.Value);
Source: Stackoverflow.com