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Element Operations (Visual Basic)

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 Visual Basic 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. 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 no such element exists or the collection does not contain exactly one element. Not applicable. Enumerable.SingleOrDefault

Queryable.SingleOrDefault

See also