TADDataSet.LoadFromStream Method

Loads a dataset's data from a stream.

Group

Links

TADDataSet Class, TADDataSet Members, uADCompDataSet Namespace, Example, public, See Also

Parameters	Description
AStream: TStream	A stream to load.
AFormat: TADStorageFormat = sfAuto	A file format. Default value is sfAuto.

Description

Use LoadFromStream to populate the dataset with data stored in an external file. The data is not moved to a database, but just loaded into a dataset in-memory storage.

AStream is the reference to the stream, containing the data to load. The stream position must be at begining of the dataset data, otherwise loading will fail.

AFormat is the file format:

sfXML - stream contains a well formed standalone XML data;
sfBinary - stream contains a binary data with custom AnyDAC format;
sfAuto - format is determined by ResourceOptions.DefaultStoreExt if it is specified, otherwise by ResourceOptions.DefaultStoreFormat.

LoadFromStream tries to load from the stream the items specified by the ResourceOptions.StoreItems. If the stream was written with different StoreItems value, then exception will be raised likes this:

[AnyDAC][Stan]-712 Cannot read [Relationlist] object

Syntax

procedure LoadFromStream(AStream: TStream; AFormat: TADStorageFormat = sfAuto);

Example

var
  oStr: TStream;
....
oStr := ADQuery1.CreateBlobStream(ADQuery1.FieldByName('data'), bmRead);
try
  ADMemTable1.LoadFromStream(oStr, sfBinary);
finally
  oStr.Free;
end;

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