Valid on NetWare, Symbian OS, UNIX, Windows and Windows CE
The WriteFile function writes data to a file.
This file content function has the following different formats:
WriteFile(handle as Integer, buffer as String) as Boolean
WriteFile(handle as Integer, buffer as String, buflen as Integer) as Boolean
WriteFile(handle as Integer, buffer as Void) as Boolean
WriteFile(handle as Integer, buffer as Void, buflen as Integer) as Boolean
Identifies a file handle returned by OpenFile or CreateFile.
Indicates a variable of any type. It stands for the buffer to be stored in the file.
Specifies the number of characters to be stored in the file. If the number of char exceeds buflen, only the first buflen characters will be stored in the file; otherwise, the whole buffer will be stored.
On successful completion, the function returns TRUE; otherwise, it returns FALSE.
Note: Do not mix the different formats of the WriteFile() function formats. Mixing the formats may lead to unexpected results.
The interpreter handles the first format (see previous) differently; and when writing the string to disk, the interpreter always adds a newline sign.
The interpreter maps the first format to a different system write function than the other three formats, which are mapped to a common system write function. The different systems write functions may use different caches to store the data written. At close time, the caches are written to disk one after another. If you mix the formats, the data may not appear in the correct sequence.
The following format is handled by the interpreter in a different way:
WriteFile(handle as Integer, buffer as String) as Boolean
When the string is written to disk, a newline is always added. This is not true for the other types of formats. Furthermore, the interpreter maps this function to a different system write function than the other three formats which were mapped to a common system write function. These different systems write functions may also use different caches to store the data written. At close time, the caches are written to disk one after another. If the formats are mixed, the data may not appear in the sequence - in which it was written. Therefore, do not mix this format with the other formats.
Example: WriteFile function
Dim fIn, fOut as integer ' Declare file handles
Dim OneLine as string ' String to hold one line
Rem First open the Input file...
fIn=OpenFile("C:\CONFIG.SYS",O_READ)
if fIn<0 then
MessageBox("Unable to open input file","Error")
Goto End
End if
Rem ...Then create the output file...
fOut=CreateFile("C:\CONFIG.BAK")
if fOut<0 then
MessageBox("Unable to create output file","Error")
CloseFile(fIn)
Goto End
End if
Rem ...Copy lines until none left...
while Not(Eof(fIn))
if ReadFile(fIn,OneLine) then WriteFile(fOut,OneLine)
wend
Rem ...Close Files, and signal success.
CloseFile(fIn)
CloseFile(fOut)
MsgBox("A backup of the CONFIG.SYS file was created","MyScript",MB_OK)
end:
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