Delphi-error

[question]

Hello,

I have made a Delphi project group and under the project I have created a new project including some unit and forms.
When I run the program ,it shows the following error-

“Zugriffsverletzung bei Adresse 0040538B in Module ‘projectName.exe’. Lesen von Adresse 00000000".


Could anybody please tell me, what does this error means?

[mkinzler]

You seem to try to access an uninitialized object ( not instantiated)

[Klaus01]

Hi,

when do you see this error message?
During programm startup?

Something is trying to access an Instance which has been created or has already been freed.

Klaus

[question]

Hi,
I have another question

I have created one form which has he following attributes:
type
TForm1 = class(TForm)
btnEnter: TButton;
btnDisplay: TButton;
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
procedure btnEnterClick(Sender: TObject);
procedure btnDisplayClick(Sender: TObject);
I have another form form2 which has its own button, but I would like to inherit the form1 into form2, but I don’t want to inherit the complete form1 ,just few functionality,such as ( btnEnter: TButton; procedure btnEnterClick(Sender: TObject) ), but I don’t have idea ,how to inherit a form partially.
Do you have any suggestion please?

[Klaus01]

Hi,

create a third unit with the button methods/procedure/actions.
This unit can then be used in form1 and form2.

Basicaly split functional things from user-interface.

Klaus

[Union]

Please tag your sourcecode. And post only one question per thread.

[Furtbichler]

Zitat:

Zitat von question (Beitrag 1222011)

Could anybody please tell me, what does this error means?

Why didn't you let google translate this for you. That's what I usually do when a stranger tells me something I don't understand.

Zitat:

Zitat von google

"Access violation at address 0040538B in module 'projectName.exe'. Read from address 00000000 ".

And almost every programmer will know what 'Read from address 0000000' means (zero, null, nil etc)