Check if instance exist?

[FaNIX]

Hi,

In delphi, how do i check if a instance of a class has already been created or not?

Something like this in VB:

Delphi-Quellcode:

        If (FtpClient Is Nothing) Then
            Return
        End If

I want to check if the Fo_FtpClient has already been created or not: Here is my code:

Delphi-Quellcode:

unit u_fdn_FTP_Dot_Net;

interface

uses
    System.Net,
    System.Net.Sockets,
    System.Text,
    System.IO,
    Borland.Vcl.Classes,
    Borland.Vcl.StrUtils,
    Borland.Vcl.SysUtils,
    Borland.Vcl.Dialogs,
    TKFP.IO,
    TKFP.Net;

type
    TFtp_Dot_Net = class(TObject)
    private
        [b]Fo_FtpClient : TKFP.Net.FtpClient;[/b]

Then before creating it again in the onclick event, i first want to check if it doesnt already exist:

Delphi-Quellcode:

Fo_FtpClient := FtpClient.Create(oLogon,Address,21);

[SubData]

hi

Delphi-Quellcode:

if not Assigned(Class) then
  Class.Create(Param):

Assigned tests if the function is nil or not.
hope this helpts.

[FaNIX]

Zitat:

Zitat von SubData

hi

Delphi-Quellcode:

if not Assigned(Class) then
  Class.Create(Param):

Assigned tests if the function is nil or not.
hope this helpts.

Thnx, works 100% :)

[DP-Maintenance]

Dieses Thema wurde von "Matze" von "Programmieren allgemein" nach "Object-Pascal / Delphi-Language" verschoben.
Delphi question