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BASIC LESSON 1 - GROUP I functions
MyLittleBase 2.0 API is divided into 7 groups of
functions
1- Initialization functions
2-Fields functions
3-Rows functions
4-Navigation functions
5-Data management functions
6-File management functions
7-Utils
This lesson deals with the
first group (Initialization functions)
and all what you can do with them.
This first group contains functions
Create (1.1)
Destroy (1.2)
Init (1.3)
Assign (1.3)
GetVersionNumber (1.4)
GetVersion (1.4)
Create and destroy are the constructor and
destructor of the mlb2 object.
Use them to create a new instance of the
object, and to free it at the end of your work. |
| DELPHI |
C++ |
To create a new
instance of mlb2 object
first add mlb2 in the uses clause of
your program:
uses forms, ..., mlb2;
then declare a new TMlb2 variable
somewhere in your class or in your programs:
var myinstance: TMlb2;
then Create your instance:
myinstance := TMlb2.Create;
Now you can apply all mlb2 api to this
instance, ex: myinstance.Init;
At the end of your work free the
instance by applying the Free method calling the Destroy destructor:
myinstance.Free;
To use the mlb2
Drag and Drop component interface
Just drag and drop the mlbc  component to
your program's form, and apply mlb2 api to this instance;
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To create a new instance of mlb2
object
first add the header file mlb2.h as include:
#include "mlb2.h";
then declare a new TMlb2 pointer
somewhere in your class or in your programs:
TMlb2* myinstance;
then Create your instance:
myinstance = myinstance->Create();
Now you can apply all mlb2 api to this
instance, ex: myinstance->Init();
At the end of your work free the
instance by calling the Destroy destructor:
myinstance->Destroy(); |
Init and Assign initializes the table content
itself.
Use Init to clear (totally erase content) any
field and row of the table before adding new fields and new data.
Assign first clears the table as Init does
then copies another table's content (all fields and rows). |
| DELPHI |
C++ |
To initialize a
mlb2 table
call the Init method from a previously
created instance:
myinstance.Init;
To Assign
another table's data to a mlb2 table
call the Assign method from a
previously created instance:
myinstance.Assign(otherinstance);
{other instance is another instance of TMlb2
object, all fields and rows are copied to myinstance object, myinstance
contains now exactly the same fields and data than otherinstance } |
To initialize a mlb2 table
call the Init method from a previously created
instance:
myinstance->Init();
To Assign
another table's data to a mlb2 table
call the Assign method from a
previously created instance:
myinstance->Assign(otherinstance); |
GetVersionNumber and GetVersion methods are used
to get the current version number of the mylittlebase library you are
using.
For sample version number of MyLittleBase 2.0
revision 0 is 200 (allways integer). |
| DELPHI |
C++ |
To get the version
number of mlb2 object
call the GetVersionNumber API:
Caption :=
IntToStr(myinstance.GetVersionNumber);
To get the version string of mlb2 object
call the GetVersion API:
Caption := myinstance.GetVersion; |
To get the version
number of mlb2 object
call the GetVersionNumber API:
printf("%d",
myinstance->GetVersionNumber());
To get the version string of mlb2 object
call the GetVersion API:
printf("%s", myinstance->GetVersion()); |
| EXERCISE 1- Use group I functions to
Initialize a new mlb2 object and to print the library's version number. |
| DELPHI |
C++ |
unit Unit1;
interface
uses
SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
Forms, Dialogs, mlb2;
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
private
mlb1: TMlb2;
public
end;
var
Form1: TForm1;
mlb: TMlb2;
implementation
{$R *.DFM}
procedure TForm1.FormCreate(Sender: TObject);
begin
mlb1 := TMlb2.Create;
mlb := TMlb2.Create;
mlb1.Assign(mlb);
{copies mlb fields and rows to mlb1}
mlb.Init;
Caption :=IntToStr(mlb.GetVersionNumber);
end;
procedure
TForm1.FormDestroy(Sender: TObject);
begin
mlb1.Free;
mlb.Free;
end;
end.
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#include <stdio.h>;
#include "mlb2.h";
int main(int argc, char* argv[]) {
TMlb2* mlb = mlb->Create();
printf("%d", mlb->GetVersionNumber());
mlb->Destroy();
} |
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