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Element operations (C#)

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Element operations return a single, specific element from a sequence.

The standard query operator methods that perform element operations are listed in the following section.

Methods

Method name Description C# query expression syntax More information
ElementAt Returns the element at a specified index in a collection. Not applicable. Enumerable.ElementAt
Queryable.ElementAt
ElementAtOrDefault Returns the element at a specified index in a collection or a default value if the index is out of range. Not applicable. Enumerable.ElementAtOrDefault
Queryable.ElementAtOrDefault
First Returns the first element of a collection, or the first element that satisfies a condition. Not applicable. Enumerable.First
Queryable.First
FirstOrDefault Returns the first element of a collection, or the first element that satisfies a condition. Returns a default value if no such element exists. Not applicable. Enumerable.FirstOrDefault
Queryable.FirstOrDefault
Queryable.FirstOrDefault<TSource>(IQueryable<TSource>)
Last Returns the last element of a collection, or the last element that satisfies a condition. Not applicable. Enumerable.Last
Queryable.Last
LastOrDefault Returns the last element of a collection, or the last element that satisfies a condition. Returns a default value if no such element exists. Not applicable. Enumerable.LastOrDefault
Queryable.LastOrDefault
Single Returns the only element of a collection or the only element that satisfies a condition. Throws an InvalidOperationException if there is no element or more than one element to return. Not applicable. Enumerable.Single
Queryable.Single
SingleOrDefault Returns the only element of a collection or the only element that satisfies a condition. Returns a default value if there is no element to return. Throws an InvalidOperationException if there is more than one element to return. Not applicable. Enumerable.SingleOrDefault
Queryable.SingleOrDefault

See also