declaring chars: char file[<nonconstant>] [1024];

This is a discussion on declaring chars: char file[<nonconstant>] [1024]; within the C++ Programming forums, part of the General Programming Boards category; is there any way to create an array of characters like this: Code: int numfiles; cin >> numfiles; char files[numfiles] ...

  1. #1
    Software Developer jverkoey's Avatar
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    declaring chars: char file[<nonconstant>] [1024];

    is there any way to create an array of characters like this:

    Code:
    int numfiles;
    cin >> numfiles;
    char files[numfiles] [1024];
    it says i need a constant variable up there, and i tried (const int)numfiles... lol, but of course, that didn't work

    so, do i have to do a typedef or whatever that command is?

    (sorry if this has already been asked)

  2. #2
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    that compiles w/out errors with mingw

  3. #3
    Software Developer jverkoey's Avatar
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    well, this is in visual studio

  4. #4
    Software Developer jverkoey's Avatar
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    ok, nevermind, i found out a way to do it (new, delete)

  5. #5
    Registered User Josh Kasten's Avatar
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    here:
    #include <iostream.h>
    #include <stdio.h>


    void main()
    {
    char **t;
    int size;

    printf("size:");
    cin>>size;

    t=new char *[size];

    for(int a=0; a<size; a++)
    t[a]=new char[1024];

    t[0]="Josh";

    printf("%s\n",t[0]);
    t[1][2]=60;
    printf("%d\n",t[1][2]);

    }
    int a; don't make a program without it.

  6. #6
    Software Developer jverkoey's Avatar
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    oook, here's what i got:

    Code:
    	int numfiles;
    	cin >> numfiles;
    	char *files;
    	files=new char[numfiles*256];
    and that creates it, to view stuff, i just do this:

    Code:
    	char filename[256];
    	strcpy(filename,"blah.txt");
    	for(int c=0;c<256;c++)
    	{
    		files[a*256+c]=filename[c];
    		if(filename[c]=='\0')
    			break;
    	}
    and just for "good housekeeping"

    Code:
    	if(files)
    		delete [] files;
    Last edited by jverkoey; 03-30-2003 at 01:47 AM.

  7. #7
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    and just for "good housekeeping"
    Code:
    if(files)
    	delete files;
    That should read "bad housekeeping". Either that, or the code should read:
    Code:
    delete[] files;
    deleting a NULL pointer has no effect, so checking for NULL before you call delete is inefficient.

  8. #8
    Registered User Josh Kasten's Avatar
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    ya and he forgot []
    int a; don't make a program without it.

  9. #9
    Registered User Josh Kasten's Avatar
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    is there a small way to do it like that with two diynamics?
    int a; don't make a program without it.

  10. #10
    Software Developer jverkoey's Avatar
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    sorry, i forgot to put the [] in there......

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