Listin Gambas2: File save

Creating a gambas2 program, step by step, a telephone index

From : http://listingambas.blogspot.com/2011/06/modulo-archivo-salvar.html

Module File: Save

Now what?, We have to save the data we entered. Clearly this is ... In the module FILE

We will create a function which verify that there is not allready such a record and avoid overwriting other data file:

EXISTS FILE
IF Exist ( target) = FALSE THEN
    'file do not exist, let us go on saving with same file name
    RETURN 1
ENDIF
' 'this part is executed when Exist and the.
IF Message.Warning ( " Existing file with type " & type "Cancel" , "Overwrite" ) = 1 THEN
' user canceled, ask for name one more time
    RETURN 2
ENDIF
IF Message.Warning ( "You decided to overwrite data, are you sure ? " , "Cancel" , "Accept" ) = 1 THEN
'has been canceled, ask again the name
    RETURN 2
ELSE
' User confirm he wants to overwrite
    RETURN 1
ENDIF
END

And now we build a routine to save data . We need to organize and store data. What way we do it?

With the order Dialog.SaveFile (), we read the path where the user wants to save the data.
We will use a string called sLine , in which are added the data separated by EndOfLine.

The code would be:

sLine & = data & EndOfLine

Separation of data: to separate the data from each other we use a scarcely-used character "|", and the variable that contains it is called EndOfLine
The first thing we will save is the data file version "v0.0.1" and version of the the program which has has done it. Why? Over time we will make improvements to the program and probably will keep data different way; so the program must know which version is the one that reads to treat them properly in memory.
We save the number of data we got (ID . COUNT )
We use a For ... Next loop to go adding in the data lines
With the command File.Save (path, lines) data are saved to a file.

PUBLIC SUB> fSave ( OPTIONAL sRoot AS String )

DIM

target AS String

DIM

AS Integer

DIM sLine AS String

DIM


EndOfLine

AS String

init: 'tag used if not willing overwrite the file, return to program at beginning of Dialog.SaveFile()

IF sRoot = ""

THEN

Dialog. Title

"Enter a filename to save the data"

Dialog. Path

Dialog. Filter

"*. lis"

"Listin Data"

a =

Dialog.

SaveFile ()

= - 1

THEN GOTO ends

IF Right $

Dialog.

Path

Len

. "lis"


)) <>

". lis" THEN

target =

Dialog. Path

& . "lis"

ELSE

target =

Dialog. Path

ENDIF

ELSE
target = sRoot

ENDIF

'Checking for file exist; if so, we ask to confirm overwriting of old one
IF CheckExist

(target,

"Phone"

= 2

THEN

GOTO init
ENDIF

'Continues to execute the program

EndOfLine =

"|"

sLine =

"v0.0.1" &


codigofinline

'reported version

sLine & =

"listin.20100718" &


codigofinline

'program that echo the file

sLine & =


var.

COUNT &


codigofinline

'number of existing records

FOR

= 0 TO


var.

COUNT -

sLine & =


var.

[a]

& EndOfLine

sLine & =


var.

dni

[a]

& EndOfLine

sLine & =


var.

name

[a]

& EndOfLine

sLine & =


var.

surname

[a]

& EndOfLine

sLine & =


var.

company[a] & EndOfLine

sLine & =


var.

position

[a] & EndOfLine

sLine & =


var.

tel_company

[a]

& EndOfLine

sLine & =


var.

tel_private

[a]

& EndOfLine

sLine & =


var.

fax

[a]

& EndOfLine

sLine & =


var.

mobile_company[a] & EndOfLine

sLine & =


var.

mobile_private

[a] & EndOfLine

sLine & =


var.

page

[a]

& EndOfLine

sLine & =


var.

photo

[a]

& EndOfLine

sLine & =


var.

address

[a]

& EndOfLine

sLine & =


var.

comments

[a]

& EndOfLine

sLine & =


var.

data_date

[a]

& EndOfLine

sLine & =


var.

mail

[a]

& EndOfLine

File . Save (


target, sLine

)

ends: 'we hit the cancel button in the dialog box Dialog.SaveFile ()

'End of the subroutine

END

And
from the form FMAIN in File / Save, we execute the code:

PUBLIC SUB


Save_Click

()

file. save

()

END

Important Note:
As you will realize, the picture files are not stored, only are the pathes where they are located.
When we move the data from one computer to another, these pictures will not appear.
See Appendix 4: packing / unpacking of data, where explains a suitable solution