DataColumnMappingCollection.GetColumnMappingBySchemaAction Method

Reference

Definition

Namespace:: System.Data.Common

Assembly:: System.Data.Common.dll

Assembly:: System.Data.dll

Assembly:: netstandard.dll

Source:: DataColumnMappingCollection.cs

Source:: DataColumnMappingCollection.cs

Source:: DataColumnMappingCollection.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

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

مشاركة عبر