You need to define "identical" here. I'm guessing you mean "have the same contents", but that is not the default definition for classes: the default definition is "are the same instance".
If you want "identical" to mean "have the same contents", you have two options:
- write a custom comparer (
IEqualityComparer<Project>
) and supply that as a parameter to Distinct
- override
Equals
and GetHashCode
on Project
There are also custom methods like DistinctBy
that are available lots of places, which is useful if identity can be determined by a single property (Id
, typically) - not in the BCL, though. But for example:
if (model != null) model = model.DistinctBy(x => x.Id).ToList();
With, for example:
public static IEnumerable<TItem>
DistinctBy<TItem, TValue>(this IEnumerable<TItem> items,
Func<TItem, TValue> selector)
{
var uniques = new HashSet<TValue>();
foreach(var item in items)
{
if(uniques.Add(selector(item))) yield return item;
}
}
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