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Core Types

DataFrame

DataType

DataTypeExpr

Expr

LazyFrame

PolarsSchema

Series

Expr Sub-namespaces

Expr.Array

Expr.Bin

Expr.Cat

Expr.Dt

Expr.Ext

Expr.List

Expr.Meta

Expr.Name

Expr.Str

Expr.Struct

Series Sub-namespaces

Series.Array

Series.Bin

Series.Cat

Series.Dt

Series.Ext

Series.List

Series.Str

Series.Struct

DataTypeExpr Sub-namespaces

DataTypeExpr.Array

DataTypeExpr.List

DataTypeExpr.Struct

DSL & Static Entrypoints

Polars

Polars.Selectors

PolarsConfig

Selector

SqlContext

LINQ Provider

LinqExtensions

PolarsGrouping

PolarsLookup

Delta & Catalog

Delta

DeltaMergeBuilder

UnityCatalog

Auxiliary Types

AmbiguousArg

AsOfTolerance

BaseExtension

Categories

ChainedWhen

CloudOptions

DataFrameMergeBuilder

DurationOrExpr

ExtensionFactory

ExtensionInfo.AsClass

ExtensionInfo.AsStorage

ExtensionInfo.NotFound

Field

FrozenCategories

GroupByBuilder

IntOrExpr

LazyFrameMergeBuilder

LazyGroupBy

MatchSchemaConfig

MergeContext

MergeSetterBuilder

MissingColumnAction

PolarsConfigScope

PolarsRowEnumerable

StringOrExpr

Then

When

Enums

On this page

ChainedWhen

Namespace: Polars.CSharp

Instance Methods

Then

csharp

public Then Then(IntoExprColumn statement)

Parameters

Name	Type	Description
`statement`	`IntoExprColumn`	-

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