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Declaration of dynamic pointer array puzzle.

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Join Date: Jul 2005

Posts: 244

Reputation: Drowzee is an unknown quantity at this point

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Drowzee

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Declaration of dynamic pointer array puzzle.

Jul 18th, 2005

Hello, everyone.

Today, I'm working on giving myself a headache.

The reason is simple. I'm rusty on, or maybe ignorant of, dynamic declaration of arrays.

What I'm doing is MFC related, but I've got the MFC questions ironed out for the most part. Now, I've got to make a good storage system for CStrings.
I want to use an array of pointers to CStrings. The problem is, I don't know how many pointers I'll need until after I've opened a text file.
But wait, it's not that simple. I've written an int-returning '\n' counter, and it goes-a-like this:

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
int textlinecount(FILE* fp)
{
	int counted = 0;
 
	while(!feof(fp))
	{
		if(getc(fp)=='\n'||feof(fp))
			counted++;
	} 
	rewind(fp);//Return to start of file for use by textreadandupdate.
	return counted;
}
int textlinecount(FILE* fp)
{
	int counted = 0;
	
	while(!feof(fp))
	{
		if(getc(fp)=='\n'||feof(fp))
			counted++;
	} 
	rewind(fp);//Return to start of file for use by textreadandupdate.
	return counted;
}

<< moderator edit: added [code][/code] tags -- learn to do so yourself >>

That should work just fine. What is wrong, though, is that this, and the CString pointer array, are part of the same class declared at startup, before a file is loaded.
Then, I use this to read in the file information.

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
BOOL TextReadAndUpdate(FILE* filetoread)
{
	char str[50];	
	while(!feof(filetoread))
	{
		for(int i=0;i<50;i++)
		{
			str[i]=getc(filetoread);
 
			if(str[i]=='\n'||feof(filetoread))
			{
				if(feof(filetoread)&&(i<50))
				{
					while(i<50)
					{						
						str[i] = ' ';
						i++;
					}
				}
				txtContents = (CString)str;
					UpdateAllViews(NULL);
				break;
			}
 
		}			
 
	}
 
	return TRUE;
}
BOOL TextReadAndUpdate(FILE* filetoread)
{
	char str[50];	
	while(!feof(filetoread))
	{
		for(int i=0;i<50;i++)
		{
			str[i]=getc(filetoread);

			if(str[i]=='\n'||feof(filetoread))
			{
				if(feof(filetoread)&&(i<50))
				{
					while(i<50)
					{						
						str[i] = ' ';
						i++;
					}
				}
				txtContents = (CString)str;
					UpdateAllViews(NULL);
				break;
			}

		}			

	}

	return TRUE;
}

<< moderator edit: added [code][/code] tags >>

Given the nature of MFC and not wanting to make the information array exist outside this 'document' class, how do I dynamically allocate a number of pointers after the class is... er... loaded..declared..initialized... by the program?

I think I should include 'CString *lineptrs;' in the header file, but I'm not sure how to continue after that.

Thank you for your time.

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