USFile.Open

Opens a file for reading, writing, or appending. Assigns an alias to the opened file. This alias can then be used in successive calls to the USFile component. The alias can also be used by the XML.Export method.

If the file is successfully opened, the alias is returned. If a failure occurs, an error message is generated.

When you have finished reading from or writing to a file that was successfully opened, close it by using the USFile.Close method.

The required and case-insensitive alias is the alias to be assigned to the successfully opened text file. This alias can be used as a file handle in subsequent calls to USFile.

The required filename specifies the folderpath and filename of the text file to be opened. This name is allowed to contain environment variables.

The optional mode is the mode in which the file is opened. Possible values are READ, WRITE and the default APPEND. Use READ to read from the opened file. Use APPEND or WRITE to write to the opened file. If you use WRITE, the existing contents of the file (if any) are lost.

CAUTION: The column alias "Mode" must be surrounded by double quotes if "Mode" is a SQL keyword on your database platform. Otherwise, double quotes around column aliases are optional.

The optional encoding is effective only when mode is APPEND or WRITE. If mode is READ, the existing encoding of the opened file applies. Possible values for encoding are: UTF-8 (the default), ASCII, and UTF16LE (= UTF-16 Little Endian).

When you open a file for read or write, as a handle for identifying that file the USFile component uses a case-insensitive prefix.alias name where prefix is "USFILE" and the separator symbol between prefix and alias is a full stop ( . ). . For example, if you open the file with alias "MyFile", the internal name is "USFILE.MYFILE".

When calling the USFile.Open method, you are allowed to spell out the prefix if you like:

INVOKE USFile.Open WITH

SELECT 'USFile.ToursFile'

, 'c:\temp\MyToursFile.txt'

, 'WRITE' "Mode"

When calling read methods of USFile other than by a full filepath, the "USFile" prefix is required.

If you call the USFile.Open repeatedly without an intervening call to USFile.Close, the second and subsequent calls lead to an error ("The alias is already in use").