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Stream Object (ADO)

Represents a stream of binary data or text.

In tree-structured hierarchies such as a file system or an e-mail system, a Record may have a default binary stream of bits associated with it that contains the contents of the file or the e-mail. A Stream object can be used to manipulate fields or records containing these streams of data. A Stream object can be obtained in these ways:

  • From a URL pointing to an object (typically a file) containing binary or text data. This object can be a simple document, a Record object representing a structured document, or a folder.

  • By opening the default Stream object associated with a Record object. You can obtain the default stream associated with a Record object when the Record is opened, to eliminate a round-trip just to open the stream.

  • By instantiating a Stream object. These Stream objects can be used to store data for the purposes of your application. Unlike a Stream associated with a URL, or the default Stream of a Record, an instantiated Stream has no association with an underlying source by default.

With the methods and properties of a Stream object, you can do the following:

  • Open a Stream object from a Record or URL with the Open method.

  • Close a Stream with the Close method.

  • Input bytes or text to a Stream with the Write and WriteText methods.

  • Read bytes from the Stream with the Read and ReadText methods.

  • Write any Stream data still in the ADO buffer to the underlying object with the Flush method.

  • Copy the contents of a Stream to another Stream with the CopyTo method.

  • Control how lines are read from the source file with the SkipLine method and the LineSeparator property.

  • Determine the end of stream position with the EOS property and SetEOS method.

  • Save and restore data in files with the SaveToFile and LoadFromFile methods.

  • Specify the character set used for storing the Stream with the Charset property.

  • Halt an asynchronous Stream operation with the Cancel method.

  • Determine the number of bytes in a Stream with the Size property.

  • Control the current position within a Stream with the Position property.

  • Determine the type of data in a Stream with the Type property.

  • Determine the current state of the Stream (closed, open, or executing) with the State property.

  • Specify the access mode for the Stream with the Mode property.

Note

URLs using the http scheme will automatically invoke the Microsoft OLE DB Provider for Internet Publishing. For more information, see Absolute and Relative URLs.

The Stream object is safe for scripting.

This section contains the following topics.

See Also

Records and Streams