DbExpressionBuilder.ThenByDescending Method (DbSortExpression, Func<DbExpression, DbExpression>, String)

.NET Framework (current version)
 

Creates a new DbSortExpression that with a sort order that includes the sort order of the given order input set together with the specified sort key in descending sort order and with the specified collation.

Namespace:   System.Data.Common.CommandTrees.ExpressionBuilder
Assembly:  System.Data.Entity (in System.Data.Entity.dll)

public static DbSortExpression ThenByDescending(
	this DbSortExpression source,
	Func<DbExpression, DbExpression> sortKey,
	string collation
)

Parameters

source
Type: System.Data.Common.CommandTrees.DbSortExpression

A DbSortExpression that specifies the ordered input set.

sortKey
Type: System.Func<DbExpression, DbExpression>

A method that specifies how to derive the additional sort key expression given a member of the input set. This method must produce an expression with an order-comparable result type that provides the sort key definition.

collation
Type: System.String

The collation to sort under.

Return Value

Type: System.Data.Common.CommandTrees.DbSortExpression

A new DbSortExpression that represents the new overall order-by operation.

Exception Condition
ArgumentNullException

source, sortKey or collation is null.

ArgumentNullException

The expression produced by sortKey is null.

ArgumentException

source does not have a collection result type.

ArgumentException

The expression produced by sortKey does not have an order-comparable string result type.

ArgumentOutOfRangeException

collation is empty or contains only space characters.

.NET Framework
Available since 4.5
Return to top
Show: