IAggregateFluentExtensionsLookupTResult, TForeignDocument, TNewResult Method (IAggregateFluentTResult, IMongoCollectionTForeignDocument, ExpressionFuncTResult, Object, ExpressionFuncTForeignDocument, Object, ExpressionFuncTNewResult, Object, AggregateLookupOptionsTForeignDocument, TNewResult) |
Appends a lookup stage to the pipeline.
Namespace:
MongoDB.Driver
Assembly:
MongoDB.Driver (in MongoDB.Driver.dll) Version: 2.17.0+b316340e6cc3a8bfc8638dc31b54fbbfe41bfcb2
Syntax public static IAggregateFluent<TNewResult> Lookup<TResult, TForeignDocument, TNewResult>(
this IAggregateFluent<TResult> aggregate,
IMongoCollection<TForeignDocument> foreignCollection,
Expression<Func<TResult, Object>> localField,
Expression<Func<TForeignDocument, Object>> foreignField,
Expression<Func<TNewResult, Object>> as,
AggregateLookupOptions<TForeignDocument, TNewResult> options = null
)
<ExtensionAttribute>
Public Shared Function Lookup(Of TResult, TForeignDocument, TNewResult) (
aggregate As IAggregateFluent(Of TResult),
foreignCollection As IMongoCollection(Of TForeignDocument),
localField As Expression(Of Func(Of TResult, Object)),
foreignField As Expression(Of Func(Of TForeignDocument, Object)),
as As Expression(Of Func(Of TNewResult, Object)),
Optional options As AggregateLookupOptions(Of TForeignDocument, TNewResult) = Nothing
) As IAggregateFluent(Of TNewResult)
[<ExtensionAttribute>]
static member Lookup :
aggregate : IAggregateFluent<'TResult> *
foreignCollection : IMongoCollection<'TForeignDocument> *
localField : Expression<Func<'TResult, Object>> *
foreignField : Expression<Func<'TForeignDocument, Object>> *
as : Expression<Func<'TNewResult, Object>> *
?options : AggregateLookupOptions<'TForeignDocument, 'TNewResult>
(* Defaults:
let _options = defaultArg options null
*)
-> IAggregateFluent<'TNewResult>
Parameters
- aggregate
- Type: MongoDB.DriverIAggregateFluentTResult
The aggregate. - foreignCollection
- Type: MongoDB.DriverIMongoCollectionTForeignDocument
The foreign collection. - localField
- Type: System.Linq.ExpressionsExpressionFuncTResult, Object
The local field. - foreignField
- Type: System.Linq.ExpressionsExpressionFuncTForeignDocument, Object
The foreign field. - as
- Type: System.Linq.ExpressionsExpressionFuncTNewResult, Object
The field in the result to place the foreign matches. - options (Optional)
- Type: MongoDB.DriverAggregateLookupOptionsTForeignDocument, TNewResult
The options.
Type Parameters
- TResult
- The type of the result.
- TForeignDocument
- The type of the foreign collection.
- TNewResult
- The type of the new result.
Return Value
Type:
IAggregateFluentTNewResultThe fluent aggregate interface.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
IAggregateFluentTResult. When you use instance method syntax to call this method, omit the first parameter. For more information, see
Extension Methods (Visual Basic) or
Extension Methods (C# Programming Guide).
See Also