DataColumnMappingCollection.GetColumnMappingBySchemaAction Method

Reference

Definition

Namespace:: System.Data.Common

Assemblies:: netstandard.dll, System.Data.Common.dll

Assembly:: System.Data.Common.dll

Assembly:: System.Data.dll

Assembly:: netstandard.dll

Source:: DataColumnMappingCollection.cs

Source:: DataColumnMappingCollection.cs

Source:: DataColumnMappingCollection.cs

Important

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Gets a DataColumnMapping for the specified DataColumnMappingCollection, source column name, and MissingMappingAction.

public:
 static System::Data::Common::DataColumnMapping ^ GetColumnMappingBySchemaAction(System::Data::Common::DataColumnMappingCollection ^ columnMappings, System::String ^ sourceColumn, System::Data::MissingMappingAction mappingAction);

public static System.Data.Common.DataColumnMapping? GetColumnMappingBySchemaAction(System.Data.Common.DataColumnMappingCollection? columnMappings, string sourceColumn, System.Data.MissingMappingAction mappingAction);

public static System.Data.Common.DataColumnMapping GetColumnMappingBySchemaAction(System.Data.Common.DataColumnMappingCollection columnMappings, string sourceColumn, System.Data.MissingMappingAction mappingAction);

static member GetColumnMappingBySchemaAction : System.Data.Common.DataColumnMappingCollection * string * System.Data.MissingMappingAction -> System.Data.Common.DataColumnMapping

Public Shared Function GetColumnMappingBySchemaAction (columnMappings As DataColumnMappingCollection, sourceColumn As String, mappingAction As MissingMappingAction) As DataColumnMapping

Parameters

columnMappings: DataColumnMappingCollection

The DataColumnMappingCollection.

sourceColumn: String

The case-sensitive source column name to find.

mappingAction: MissingMappingAction

One of the MissingMappingAction values.

Returns

DataColumnMapping

A DataColumnMapping object.

Exceptions

InvalidOperationException

The mappingAction parameter was set to Error, and no mapping was specified.

Examples

The following example searches for a DataColumnMapping with the given source column name within the collection. If the object exists, it is returned. The example assumes that a DataColumnMappingCollection collection and a DataColumnMapping object have been created.

public void FindDataColumnMapping()
{
    // ...
    // create mappings and mapping
    // ...
    if (mappings.Contains("Description"))
        mapping = DataColumnMappingCollection.GetColumnMappingBySchemaAction
            (mappings, "Description", MissingMappingAction.Ignore);
}

Public Sub FindDataColumnMapping()
    ' ...
    ' create mappings and mapping
    ' ...
    If mappings.Contains("Description") Then
        mapping = _
           DataColumnMappingCollection.GetColumnMappingBySchemaAction _
           (mappings, "Description", MissingMappingAction.Ignore)
    End If
End Sub

Remarks

If the DataColumnMapping exists in the collection, it is returned.

If the DataColumnMapping does not exist in the collection, for a given MissingMappingAction, the following actions occur:

MissingMappingAction	Action Taken
`Passthrough`	Creates a DataColumnMapping with the specified source column name as both the source column name and the DataSet column name. This DataColumnMapping is not added to the collection.
`Error`	An InvalidOperationException is generated if the specified column mapping is missing.
`Ignore`	Gets a null value.

Applies to

Produkt	Verzie
.NET	Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1

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