共用方式為


Query Keywords (C# Reference)

This section contains the contextual keywords used in query expressions.

In This Section

Clause

Description

from

Specifies a data source and a range variable (similar to an iteration variable).

where

Filters source elements based on one or more Boolean expressions separated by logical AND and OR operators ( && or || ).

select

Specifies the type and shape that the elements in the returned sequence will have when the query is executed.

group

Groups query results according to a specified key value.

into

Provides an identifier that can serve as a reference to the results of a join, group or select clause.

orderby

Sorts query results in ascending or descending order based on the default comparer for the element type.

join

Joins two data sources based on an equality comparison between two specified matching criteria.

let

Introduces a range variable to store sub-expression results in a query expression.

in

Contextual keyword in a join clause.

on

Contextual keyword in a join clause.

equals

Contextual keyword in a join clause.

by

Contextual keyword in a group clause.

ascending

Contextual keyword in an orderby clause.

descending

Contextual keyword in an orderby clause.

See Also

Reference

C# Keywords

Concepts

LINQ Query Expressions (C# Programming Guide)

Other Resources

LINQ (Language-Integrated Query)

Getting Started with LINQ in C#