PipelineDefinitionBuilderLookupTInput, TIntermediate, TForeignDocument, TOutput Method (PipelineDefinitionTInput, TIntermediate, IMongoCollectionTForeignDocument, ExpressionFuncTIntermediate, Object, ExpressionFuncTForeignDocument, Object, ExpressionFuncTOutput, Object, AggregateLookupOptionsTForeignDocument, TOutput) |
Appends a lookup stage to the pipeline.
Namespace:
MongoDB.Driver
Assembly:
MongoDB.Driver (in MongoDB.Driver.dll) Version: 2.8.0+cc573f3e1f48f39162b4b680e921a623e127e8fa
Syntax public static PipelineDefinition<TInput, TOutput> Lookup<TInput, TIntermediate, TForeignDocument, TOutput>(
this PipelineDefinition<TInput, TIntermediate> pipeline,
IMongoCollection<TForeignDocument> foreignCollection,
Expression<Func<TIntermediate, Object>> localField,
Expression<Func<TForeignDocument, Object>> foreignField,
Expression<Func<TOutput, Object>> as,
AggregateLookupOptions<TForeignDocument, TOutput> options = null
)
<ExtensionAttribute>
Public Shared Function Lookup(Of TInput, TIntermediate, TForeignDocument, TOutput) (
pipeline As PipelineDefinition(Of TInput, TIntermediate),
foreignCollection As IMongoCollection(Of TForeignDocument),
localField As Expression(Of Func(Of TIntermediate, Object)),
foreignField As Expression(Of Func(Of TForeignDocument, Object)),
as As Expression(Of Func(Of TOutput, Object)),
Optional options As AggregateLookupOptions(Of TForeignDocument, TOutput) = Nothing
) As PipelineDefinition(Of TInput, TOutput)
[<ExtensionAttribute>]
static member Lookup :
pipeline : PipelineDefinition<'TInput, 'TIntermediate> *
foreignCollection : IMongoCollection<'TForeignDocument> *
localField : Expression<Func<'TIntermediate, Object>> *
foreignField : Expression<Func<'TForeignDocument, Object>> *
as : Expression<Func<'TOutput, Object>> *
?options : AggregateLookupOptions<'TForeignDocument, 'TOutput>
(* Defaults:
let _options = defaultArg options null
*)
-> PipelineDefinition<'TInput, 'TOutput>
Parameters
- pipeline
- Type: MongoDB.DriverPipelineDefinitionTInput, TIntermediate
The pipeline. - foreignCollection
- Type: MongoDB.DriverIMongoCollectionTForeignDocument
The foreign collection. - localField
- Type: System.Linq.ExpressionsExpressionFuncTIntermediate, Object
The local field. - foreignField
- Type: System.Linq.ExpressionsExpressionFuncTForeignDocument, Object
The foreign field. - as
- Type: System.Linq.ExpressionsExpressionFuncTOutput, Object
The "as" field. - options (Optional)
- Type: MongoDB.DriverAggregateLookupOptionsTForeignDocument, TOutput
The options.
Type Parameters
- TInput
- The type of the input documents.
- TIntermediate
- The type of the intermediate documents.
- TForeignDocument
- The type of the foreign collection documents.
- TOutput
- The type of the output documents.
Return Value
Type:
PipelineDefinitionTInput,
TOutput
The fluent aggregate interface.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
PipelineDefinitionTInput,
TIntermediate. 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