Solved

THOSE ERROR MESSAGE ABOUT?

Posted on 2000-03-19
3
323 Views
Last Modified: 2006-11-17
I JUST USE THE C++ BUILDER 4.0.
MY SOURCE IS:
void __fastcall TForm1::Button1Click(TObject *Sender)
{
TChart::TDBChart *dbc=new TDBChart();

dbc->Assign(DBChart1->Picture->Bitmap);

// TJPEGImage ¤º©wªºÀ£ÁY²v¬O90%
dbc->CompressionQuality=(short)Edit1->Text.ToInt();

dbc->SaveToBitmapFile("Test.bmp");

//±N¦sªºJPG¹ÏŪ¨ìImage2
// JPG->LoadFromFile("test.jpg");

// Image2->Picture->Bitmap->Assign(JPG);

delete dbc;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormClose(TObject *Sender, TCloseAction &Action)
{
if (CheckBox1->Checked)
   DeleteFile("Test.bmp");
}

THE ERROR MESSAGE IS:
[C++ Error] TEST.cpp(18): E2451 Undefined symbol 'TDBChart'.
[C++ Error] TEST.cpp(18): E2451 Undefined symbol 'dbc'.
[C++ Error] TEST.cpp(18): E2285 Could not find a match for 'TDBChart::TDBChart()'.
[C++ Error] TEST.cpp(20): E2316 'Picture' is not a member of 'TDBChart'.
[C++ Error] TEST.cpp(23): E2451 Undefined symbol 'Edit1'.
[C++ Error] TEST.cpp(32): E2158 Operand of 'delete' must be non-const pointer.
THOSE ERROR ABOUT WHAT?
THANK YOU!

0
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Question by:erichuang
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3 Comments
 
LVL 31

Expert Comment

by:Zoppo
ID: 2635408
Hi erichuang,

I found at least one failure:

If TDBChart is declared in namespace of TChart, then
TChart::TDBChart *dbc=new TDBChart();
should be:
TChart::TDBChart *dbc=new TChart::TDBChart();

this should solve the first three and the last error.

the other errors seem to be declaration errors.
Unfortunately I'm not experienced with C++ builder, so I don't know the TDBChart class at all...

ZOPPO
0
 

Accepted Solution

by:
amador earned 80 total points
ID: 2639808
1 - the compilator cant find the obj TDBChat
2 - Consequence of 1
3 - He cant find the constructor TDBChart in obj TDBChart, if TDBChart is derived for TChart, put TChart:: before.
4 - He cant finda the function Picture in TDBChart, see 3
5 - Verify if Edit1 is declared, or if it is the name of the object really.
6 - Consequence of 1.

TChart::TDBChart *dbc= (TDBChart *) new TChart::TDBChart();

Test pointer before: if (dbc == NULL) return;

0
 
LVL 31

Expert Comment

by:Zoppo
ID: 2639894
Hi amador,

some comments:

>if TDBChart is derived for TChart, put TChart:: before.
derived??? I would say TDBChart is declared in namespace TChart, i.e. a 'subclass' of TChart...

>He cant finda the function Picture in TDBChart
From the code I would say 'object Picture' instead of 'function Picture'

>TChart::TDBChart *dbc= (TDBChart *) new TChart::TDBChart();
why use that extra cast (which will not work until you cast to (TCart::TDBChart*)new... ), it's not needed

ZOPPO
0

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