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Element Operations

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

Visual Basic Query Expression Syntax

More Information

ElementAt

Returns the element at a specified index in a collection.

Not applicable.

Not applicable.

Enumerable.ElementAt<TSource>

Queryable.ElementAt<TSource>

ElementAtOrDefault

Returns the element at a specified index in a collection or a default value if the index is out of range.

Not applicable.

Not applicable.

Enumerable.ElementAtOrDefault<TSource>

Queryable.ElementAtOrDefault<TSource>

First

Returns the first element of a collection, or the first element that satisfies a condition.

Not applicable.

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.

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.

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.

Not applicable.

Enumerable.LastOrDefault

Queryable.LastOrDefault

Single

Returns the only element of a collection, or the only element that satisfies a condition.

Not applicable.

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.

Not applicable.

Enumerable.SingleOrDefault

Queryable.SingleOrDefault

See Also

Tasks

How to: Query for the Largest File or Files in a Directory Tree (LINQ)

Reference

System.Linq

Concepts

Standard Query Operators Overview