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Transfer data from the server and store it in a local buffer.
Syntax
object.GetData( Resource, Buffer,
[Length], [Options] )
Parameters
- Resource
- A string that specifies the resource on the server that will be
accessed. If the resource specifies a file, then the contents of
the file will be returned to the server. If the resource specifies
a script or other executable content, it will be executed and the
output will be transferred to the local system. The file pathing
and name conventions must be that of the server.
- Buffer
- This parameter specifies the local buffer that the data will be
stored in. If the variable is a String type, then the data will be
returned as a string of characters. This is the most appropriate
data type to use if the file on the server is a text file. If the
remote file contains binary data, it is recommended that a Byte
array variable be specified as the argument to this method.
- Length
- An optional integer argument that will contain the number of
bytes copied into the buffer when the method returns.
- Options
- An optional integer value which specifies one or more options.
This argument is constructed by using a bitwise operator with any
of the following values:
Value |
Constant |
Description |
0 |
httpTransferDefault |
The default transfer mode. The resource data is downloaded to
the local system exactly as it is stored on the server. If you
are requesting a text-based resource, the data may use a
different end-of-line character sequence. For example, the
end-of-line character may be a single linefeed character instead
of a carriage return and linefeed pair. |
1 |
httpTransferConvert |
If the resource being downloaded from the server is
textual, the data is automatically converted so that the end of
line character sequence is compatible with the Windows
platform. Individual carriage return or linefeed characters are
converted to carriage return/linefeed character sequences. |
2 |
httpTransferCompress |
This option informs the server that the client is willing
to accept compressed data. If the server supports compression
for the specified resource, then the data will be automatically
expanded before being returned to the caller. This option is
selected by default if compression has been enabled by setting
the Compression property to True. |
4 |
httpTransferErrorData |
This option causes the client to accept error data from the
server if the request fails. If this option is specified, an
error response from the server will not cause the method to
fail. Instead, the response is returned to the client and the
method will succeed. If this option is used, your application
should check the ResultCode property to obtain the
HTTP status code returned by the server. This will enable you to
determine if the operation was successful. |
Return Value
A value of zero is returned if the operation was successful,
otherwise a non-zero error code is returned which indicates the cause
of the failure.
Remarks
The GetData method transfers data from the server to the
local system, storing it in the specified buffer . This method will
cause the current thread to block until the file transfer completes,
a timeout occurs or the transfer is canceled. During the transfer,
the OnProgress event will fire periodically, enabling the
application to update any user interface objects such as a progress
bar.
Specifying the httpTransferCompress option does not guarantee
that the data returned by the server will actually be compressed, it
only informs the server that the client is willing to accept compressed
data. Whether or not a particular resource is compressed depends on the
server configuration, and the server may decide to only compress certain
types of resources, such as text files.
If compression has been enabled and the server returns compressed
data, it will be automatically expanded before being returned to the
caller. If the application is using the OnProgress event to
determine the amount of data being returned by the server, it is
important to keep in mind that the values reflect the size of the
compressed data.
See Also
Compression Property,
GetFile Method,
PutData Method,
PutFile Method,
OnProgress Event
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