SqlExpressionFactory.Case 方法

定义

命名空间:: Microsoft.EntityFrameworkCore.Query

程序集:: Microsoft.EntityFrameworkCore.Relational.dll

程序包:: Microsoft.EntityFrameworkCore.Relational v3.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v3.1.0

程序包:: Microsoft.EntityFrameworkCore.Relational v5.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v6.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v10.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v11.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v7.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v8.0.0

程序包:: Microsoft.EntityFrameworkCore.Relational v9.0.0

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

重载

名称	说明
Case(SqlExpression, CaseWhenClause[])	已过时. 创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。
Case(IReadOnlyList<CaseWhenClause>, SqlExpression)	创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。
Case(SqlExpression, SqlExpression, CaseWhenClause[])
Case(SqlExpression, IReadOnlyList<CaseWhenClause>, SqlExpression)	创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。
Case(SqlExpression, IReadOnlyList<CaseWhenClause>, SqlExpression, SqlExpression)	创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。

Case(SqlExpression, CaseWhenClause[])

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

注意

Use overload which takes IReadOnlyList instead of params

创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression operand, params Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] whenClauses);

[System.Obsolete("Use overload which takes IReadOnlyList instead of params")]
public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression operand, params Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] whenClauses);

abstract member Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression
override this.Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression

[<System.Obsolete("Use overload which takes IReadOnlyList instead of params")>]
abstract member Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression
override this.Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression

Public Overridable Function Case (operand As SqlExpression, ParamArray whenClauses As CaseWhenClause()) As CaseExpression

参数

operand: SqlExpression

要与 Test in whenClauses进行比较的表达式。

whenClauses: CaseWhenClause[]

要 CaseWhenClause 比较和获取结果的列表。

CaseExpression

表示 SQL 树中 CASE 语句的表达式。

实现

Case(SqlExpression, CaseWhenClause[])

特性: ObsoleteAttribute

适用于

Case(IReadOnlyList<CaseWhenClause>, SqlExpression)

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression Case(System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> whenClauses, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? elseResult);

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> whenClauses, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression elseResult);

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> whenClauses, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? elseResult);

abstract member Case : System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression
override this.Case : System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression

abstract member Case : System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression
override this.Case : System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression

Public Overridable Function Case (whenClauses As IReadOnlyList(Of CaseWhenClause), elseResult As SqlExpression) As SqlExpression

Public Overridable Function Case (whenClauses As IReadOnlyList(Of CaseWhenClause), elseResult As SqlExpression) As CaseExpression

参数

whenClauses: IReadOnlyList<CaseWhenClause>

要评估条件并从中获取结果的列表 CaseWhenClause 。

elseResult: SqlExpression

如果没有匹配项，则 whenClauses 返回的值（如果有）。

SqlExpression

CaseExpression

表示 SQL 树中 CASE 语句的表达式。

实现

Case(IReadOnlyList<CaseWhenClause>, SqlExpression)

适用于

Case(SqlExpression, SqlExpression, CaseWhenClause[])

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression operand, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression elseResult, params Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] whenClauses);

abstract member Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression
override this.Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause[] -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression

Public Overridable Function Case (operand As SqlExpression, elseResult As SqlExpression, ParamArray whenClauses As CaseWhenClause()) As CaseExpression

参数

operand: SqlExpression

elseResult: SqlExpression

whenClauses: CaseWhenClause[]

CaseExpression

适用于

Case(SqlExpression, IReadOnlyList<CaseWhenClause>, SqlExpression)

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression operand, System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> whenClauses, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression elseResult);

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression Case(Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? operand, System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> whenClauses, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? elseResult);

abstract member Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression
override this.Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseExpression

Public Overridable Function Case (operand As SqlExpression, whenClauses As IReadOnlyList(Of CaseWhenClause), elseResult As SqlExpression) As CaseExpression

参数

operand: SqlExpression

要与 Test in whenClauses进行比较的表达式。

whenClauses: IReadOnlyList<CaseWhenClause>

要 CaseWhenClause 比较和获取结果的列表。

elseResult: SqlExpression

如果没有匹配项，则 whenClauses 返回的值（如果有）。

CaseExpression

表示 SQL 树中 CASE 语句的表达式。

实现

Case(SqlExpression, IReadOnlyList<CaseWhenClause>, SqlExpression)

适用于

Case(SqlExpression, IReadOnlyList<CaseWhenClause>, SqlExpression, SqlExpression)

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

Source:: SqlExpressionFactory.cs

创建一个表示 SQL 树中的 CASE 语句的新 CaseExpression 项。

public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression Case(Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? operand, System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> whenClauses, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? elseResult, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression? existingExpression = default);

abstract member Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression
override this.Case : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * System.Collections.Generic.IReadOnlyList<Microsoft.EntityFrameworkCore.Query.SqlExpressions.CaseWhenClause> * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression

Public Overridable Function Case (operand As SqlExpression, whenClauses As IReadOnlyList(Of CaseWhenClause), elseResult As SqlExpression, Optional existingExpression As SqlExpression = Nothing) As SqlExpression