[Gambas-user] casting, macro change from str to resultfield?

[Muriel Bodard]

Le Mardi 03 Janvier 2006 10:29, johnf a écrit :
> On Tuesday 03 January 2006 01:10, ron wrote:
> > On Tuesday 03 January 2006 08:34, johnf wrote:
> > > On Monday 02 January 2006 23:30, johnf wrote:
> > > > On Monday 02 January 2006 23:18, ron wrote:
> > > > > oopfield = hfield.Value
> > > >
> > > > Thanks that should work.
> > > >
> > > > But I also realized that Gambas is a compiled lang - therefore there
> > > > is nothing like macro substitution....
> > > >
> > > > Thanks again
> > > > John
> > >
> > > Dam I thought you had the answer.  But hfield does not have "Value".
> > >
> > > But I wonder if something else does?  I'll continue to check.
> > > BTW I'm using 1.9.23
> > > Thanks
> > > John
> >
> > Did a look in the help
> > gb.db.result:
> >
> >
> > DIM hResult AS Result
> > DIM aVariant AS Variant
> >
> > aVariant = hResult [ Field AS String ]
> >
> >
> > Returns the value of a field in the current record of the Result object.
> >
> > should be then:
> >
> > FOR EACH hfield IN contactdata.Fields
> >   INC i
> >   loopfield = contactdata[hfield.Name]
> >   contacts[c, i].Text = loopfield
> > NEXT
> >
> > contactdata = result
> > contacts = gridview
> >
> > I hoop this wil do the job.
> >
> > Ron
>
> This works thank you very much.  It's 1:am here and I'm very tired so I'm
> going to bed.  But I want to understand your process of determining the
> correct way to get to the field.  I need to be able to do the same thing.
> But when I read the help file I did not understand the notation.  But you
> did!  So if you can take some more time could you explain it.  If this like
> trying to explain OOP then don't of course.  But maybe there is some link
> or text in the help file that will explain the notation?
>
> Again thanks
>
>
>
> PS I think have a little understanding as I re-read the message.  Is
> aVariant one of my controls (or any data type?).
>
> John


What is this code ...; ?

i understand that you can't understand that !

The code can work but is not writing on a good way to be use at a sample:


First :

What a Result :
A result is a buffer that store a query result. (i think you have understand 
that.

When you send a query like Myconnection.exec("Select id, user from mytable" )
You obtain a result with n records on 2 fields

Result is a class too so:

you can access to the current record by :
	- hResult!Field
	- hResult["field"]

But you can access to the other result info like
- record count
- connection parent
- Index of current record
- Record walking functions
- ResultFields (collection of the fields used in the result)


ResultField
- name
- Length (max length)
- Result (parent)
- Type (type of data)



this Fill a tableview with a gived result
You need a form with a Tableview named TableView1 and a textBox named textbox1

' Gambas class file

PRIVATE hResult AS Result
PRIVATE hCon AS NEW Connection

PUBLIC SUB _New()

  DIM hrField AS ResultField

  hCon.Type = "sqlite"
  hCon.Login = ""
  hCon.PassWord = ""
  hCon.Host = "/home/fabien/.Gestion"
  hCon.Name = "Dossieryzf"
  hCon.Open

  hResult = hCon.Exec("SELECT * FROM Ecritures")


  'Fill the columns headers of the Tableview an set number of columns
  FOR EACH hrField IN hResult.Fields
    INC TableView1.Columns.Count
    TableView1.Columns[TableView1.Columns.Count - 1].Text = hrField.Name
  NEXT

  'Set The table view Number of Rows
   TableView1.Rows.Count = hResult.Count

END

PUBLIC SUB TableView1_Data(Row AS Integer, Column AS Integer)

  'Move to the Queried Row value
  hResult.MoveTo(Row)
  'Set The Current Cell Value With the current column header text for the
  'fieldname

  TableView1.Data.Text = hResult[TableView1.Columns[Column].Text]

  'Toggle Row Color 1 on 2 (more pretty)
  TableView1.Data.Background = IIf(row MOD 2 > 0, color.TextBackground, 
&HF0EEFF&)

END

PUBLIC SUB Form_Close()
  hResult = NULL
  hCon.Close

END



I hope it help you...

Gambas is a powerfull tool to manage databases... Not so complete as a dedied 
tool but mabe one of the better db layer i know.


The next Lesson ..; on how to add datas... and i'm going to try data 
management on big tables...

Regards,
Fabien Bodard