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static variable in mfc

Posted on 2001-07-26
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Last Modified: 2013-11-20
I would like to use a static variable as member data of an class in an mfc dialog based application.Here where should I do forward declaration?

eg:

class dlgMyclass
{
  static int a;
  public:
  void say()
  {
     AfxMessageBox("hi");
   }
};

where to do forward declaration i.e.  int dlgMyclass::a;

Please suggest me the solution for this.
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Question by:joshig
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3 Comments
 
LVL 86

Accepted Solution

by:
jkr earned 50 total points
ID: 6322104
>>where to do forward declaration i.e.  int dlgMyclass::a;

You don't need a foward declaration, all you have to do is instantiating storage space for the variable:

class dlgMyclass
{
 static int a;
 public:
 void say()
 {
    AfxMessageBox("hi");
  }
};

int dlgMyclass::a = 0;
0
 
LVL 30

Expert Comment

by:Axter
ID: 6323901
FYI,
Adding to jkr comment, you usally want to put the implementation in the *.cpp file.
So
//Put in header (*.h) file
class dlgMyclass
{
static int a;
public:
void say()
{
   AfxMessageBox("hi");
 }
};
/////////////////////////////////

//Put in source (*.cpp) file
int dlgMyclass::a = 0;

0
 
LVL 23

Expert Comment

by:Roshan Davis
ID: 9490562
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:

Answered by : jkr

Please leave any comments here within the next seven days.

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

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