Entry

Delphi: Array: 1D: Search: Simple: How search in a 1-dimensional array? [parameter pass procedure]

Nov 14th, 2003 08:22
Knud van Eeden,

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--- Knud van Eeden --- 10 November 2003 - 10:23 pm -------------------

Delphi: Array: 1D: Search: Simple: How search in a 1-dimensional 
array? [parameter pass procedure]

---

Steps: Overview:

 1. -Create a new application in Delphi

 2. -Put a button on the form

 3. -Double click on the button

 4. -As data e.g. the following is given.
     The 1-dimensional array with its data

       [0] = 0
       [1] = 1
       [2] = 2
       [3] = 3
       [4] = 4
       [5] = 5
       [6] = 6
       [7] = 7
       [8] = 8

     and the element you are looking for
     is e.g. 4.

 5. -To search use e.g. a linear search
     through all the elements of the array
     until the element is found

      Thus in pseudocode:

        for column = columnfirst to columnlast
         if element is found in array( column ) then message found
        end

 6. -Thus this might become in Delphi:

var j : integer;

begin

 for i := Low( myarray ) to High( myarray ) do begin

   if ( myarray[ i ] ) = integersearchI then begin

    ShowMessage( Format( '[ %d ] -> %d', [ i, myarray[ i ] ] ) );

   end;

  end;

 end;

 6. -So all together this might give the following source code:

--- cut here ---------------------------------------------------------

// --- MAIN --- //

unit Unit1;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, 
Forms,

  Dialogs, StdCtrls;

type

 Tmyarray = array[0..8] of integer;

type

  TForm1 = class(TForm)

    Button1: TButton;

// --- FUNCTION: HEADER: BEGIN --- //

    procedure Button1Click(Sender: TObject);

    procedure PROCArrayInitializeSearchElement( var myarray : 
Tmyarray );

    procedure PROCArraySearchElementMain;

    procedure PROCArrayViewSearchElement( integersearchI : integer; 
myarray : Tmyarray );

// --- FUNCTION: HEADER: END --- //

  private

    { Private declarations }

  public

    { Public declarations }

  end;

var

  Form1: TForm1;

implementation

{$R *.dfm}

// Set range checking on

{$R+}

procedure TForm1.Button1Click(Sender: TObject);

begin

 PROCArraySearchElementMain;

end;

// --- LIBRARY --- //

// library: array: view: search: element [kn, ni, fr, 14-11-2003 
15:14:22]

procedure TForm1.PROCArrayInitializeSearchElement( var myarray : 
Tmyarray );

begin

 myarray[ 0 ] := 0;

 myarray[ 1 ] := 1;

 myarray[ 2 ] := 2;

 myarray[ 3 ] := 3;

 myarray[ 4 ] := 4;

 myarray[ 5 ] := 5;

 myarray[ 6 ] := 6;

 myarray[ 7 ] := 7;

 myarray[ 8 ] := 8;

end;

// library: array: view: search: element [kn, ni, fr, 14-11-2003 
15:14:22]

procedure TForm1.PROCArraySearchElementMain;

 // e.g. // Set range checking on

 // e.g. {$R+}

 // e.g.

 // e.g. type

 // e.g.  Tmyarray = array[0..8] of integer;

 // e.g.

 // e.g. PROCArraySearchElementMain;

var myarray : Tmyarray;

begin

 PROCArrayInitializeSearchElement( myarray );

 PROCArrayViewSearchElement( 4, myarray );

end;

// library: array: view: search: element [kn, ni, fr, 14-11-2003 
15:14:22]

procedure TForm1.PROCArrayViewSearchElement( integersearchI : integer; 
myarray : Tmyarray );

 // e.g. type

 // e.g.  Tmyarray = array[0..8] of integer;

 // e.g.

 // e.g. var myarray : Tmyarray;

 // e.g. PROCArrayViewSearchElement( 4, myarray );

var i : integer;

var j : integer;

begin

 for i := Low( myarray ) to High( myarray ) do begin

   if ( myarray[ i ] ) = integersearchI then begin

    ShowMessage( Format( '[ %d ] -> %d', [ i, myarray[ i ] ] ) );

   end;

  end;

 end;

end.

--- cut here ---------------------------------------------------------

 6. -If you run this program, you will see a message box showing:

  +-----------------------+
  |                       |
  |  Found 4 at [ 4 ]     |
  |                       |
  |        +------+       |
  |        |  OK  |       |
  |        +------+       |
  |                       |
  +-----------------------+

---
---

Internet: see also:

---

Delphi: Array: 2D: Search: Simple: How search in a 2-dimensional 
array? [parameter pass procedure]
http://www.faqts.com/knowledge_base/view.phtml/aid/26482/fid/175

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