QFilestream Properties
| Field | Type | R/W | Default | Support |
| EOF | INTEGER | R | WXG | |
| EOF specifies whether the file pointer has reached the end of file. | ||||
| Handle | INTEGER | R | W | |
| LineCount | INTEGER | R | WXG | |
| LineCount determines how many lines there are in the file. Note that LineCount ignores the CR character, and will only detect LF, so it treats CRLF as one line, but LFLF as 2 lines. | ||||
| Position | INTEGER | RW | WXG | |
| Position specifies the current position of the file pointer, any read/write operations will begin from here. | ||||
| Size | INTEGER | R | WXG | |
| Size determines the size of the file in bytes. | ||||
QFilestream Methods
| Method | Type | Description | Params | Support |
| Close | SUB | Close the stream | 0 | WXG |
| CopyFrom | SUB (Stream, Bytes%) | Copy from another stream Either QFileStream or QMemoryStream If Bytes%=0 then the whole stream is copied |
2 | W |
| Use CopyFrom to copy a QFILESTREAM or a
QMEMORYSTREAM to the current filestream. Details: If Bytes% = 0 then the Stream is reset to position 0 and the whole stream is then copied. Example:
|
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| ExtractRes | SUB (Resource AS LONG) | Extract resource to filestream | 1 | WXG |
| Extracts a resource from your program to
the filestream. Details: The parameter Resource is not the resource handle, but the absolute position of the resource within your file. This requires that you use the keyword Resource(n) to specify the resource number. Example (dumping all resources):
|
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| LoadArray | SUB (Array(), NumElements&) | Load data into array | 2 | WXG |
| Open | SUB (FileName$, Method%) | Open a file, Method% see RAPIDQ.INC '-- File Mode CONST fmCreate = 65535 CONST fmOpenRead = 0 CONST fmOpenWrite = 1 CONST fmOpenReadWrite = 2 -------------------------------------------------- QFileStream is not a SUB as stated in the RQ HTML Documentation, it's a FUNCTION which returns ZERO when the file dont on Open Failure. See example below. |
2 | WXG |
| Read | SUB (variable) | Generic Read, determines the storage space and saves data in variable | 1 | WXG |
| Datasize is automatically determined, and
the value is stored into the variable. Example:
|
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| ReadLine | FUNCTION () AS STRING | Reads an entire line, supports UNIX files | 0 | WXG |
| ReadNum | FUNCTION (Num_Type) AS DOUBLE | Returns number '-- ie. PRINT File.ReadNum(Num_SINGLE) Num_Type can be next |
1 | WXG |
| ReadBinStr | FUNCTION (n) AS STRING | Read n bytes, returns the binary string | 1 | WXG |
| ReadStr | FUNCTION (n) AS STRING | Read n bytes, returns the text string | 1 | WXG |
| ReadUDT | SUB (MyType) | Read and store data in a MyType structure | 1 | WXG |
| SaveArray | SUB (Array(), NumElements&) | Save array | 2 | WXG |
| Seek | SUB (Position%, From%) | Seek to Position%, From% see RAPIDQ.INC '-- Offsets CONST soFromBeginning = 0 '-- Seek (offset) from Beginning CONST soFromCurrent = 1 '-- Seek (offset) from Current position CONST soFromEnd = 2 '-- Seek (offset) from End |
2 | WXG |
| Write | SUB (variable) | Generic Write, determines the storage space and saves data to file | 1 | WXG |
| WriteLine | SUB (S AS STRING) | Writes string with CR+LF | 1 | WXG |
| WriteNum | SUB (number, bytes%) | Writes a number to file | 2 | WXG |
| WriteBinStr | SUB (string, bytes%) | Writes a binary string to file | 2 | WXG |
| WriteStr | SUB (string, bytes%) | Writes a text string to file (fast) | 2 | WXG |
| WriteUDT | SUB (MyType) | Write data stored in a MyType structure | 1 | WXG |
$INCLUDE "RAPIDQ.INC"
DIM File AS QFileStream
File.Open("test.bas", fmOpenRead)
S$ = File.ReadStr(File.Size) '' Read entire file
PRINT S$ '' print it
File.Close
'------------------------------------------------------
$INCLUDE "RAPIDQ.INC"
TYPE MyType
Name AS STRING*30
Phone AS STRING*8
Age AS INTEGER
END TYPE
DIM Person AS MyType
Person.Name = "Joe"
Person.Phone = "555-5555"
DIM File AS QFileStream
File.Open("test", fmCreate)
File.WriteUDT(Person)
'--------------------------------------------------------------------
Up to now
QFilestream.Open ("MyFile", fmOpenRead) BUGGED at RUNTIME
when there is a 'problem' : file dont exist, file already opened, ...
Something like this can trap the error and save you !
' -----------------
iOpenCount = 0
Do
iOpenCount ++
Sleep (0.5)
If iOpenCount = 4 Then ShowMessage ("Cannot Open File " & dumpPathFile): Exit Sub
Loop Until dumpFile.Open (dumpPathFile, fmOpenRead)
' DO YOUR STUFF HERE
dumpFile.Close
' ------------------
Maybe you all knew that except me :)
Jacques
Actually, the Open method of a QFileStream may fail for other reasons
than the file's not existing. For example, if another program has an
exclusive lock on the file, your program will not be able to open it.
Also, permissions may be set in such a way that your program could
write to the file but not open it to read it (on NTFS and Linux files
systems). Better error checking includes tests for both existence and
successful opening.
Stylistically, I dislike your code because I always use block IF
statements. However, this is not a requirement; I just find that it
follows the paradigm of structural programming better.
This is a skeleton of my file I/O error checking routines:
'Begin RapidQ Code
CONST ERR_CRITICAL = &H0001
CONST ERR_WARNING = &H0002
CONST ERR_INFO = &H0004
CONST ERR_QUESTION = &H0008
CONST ERR_ASSERT = &H1000
CONST ERR_FILE = &H2000
CONST ERR_INPUT = &H4000
CONST ERR_INTERNAL = &H8000
CONST ERR_EXCEPTION = &HF000
DECLARE SUB HandleError (message AS STRING, type AS INTEGER)
CONST FILENAME = "file.ext"
DIM file AS QFILESTREAM
IF FILEEXISTS (FILENAME) <> False THEN
IF File.Open (FileName, fmOpenRead) <> False THEN
'Do file stuff
File.Close
ELSE
HandleError ("The file could not be opened. Check your permissions.", ERR_CRITICAL OR ERR_FILE)
'More Stuff
END IF
ELSE
HandleError("The file could not be opened. Be sure it exists.", ERR_CRITICAL OR ERR_FILE)
'More Stuff
END IF
'End RapidQ Code
--
Chris
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