help needed
CodeGuru Home VC++ / MFC / C++ .NET / C# Visual Basic VB Forums Developer.com
Results 1 to 2 of 2

Thread: help needed

Hybrid View

  1. #1
    Join Date
    Mar 2013
    Posts
    11

    help needed

    what is the difference between unsigned char in[] and const unsigned char in[]

    Thanks

  2. #2
    Join Date
    Dec 2012
    Location
    England
    Posts
    2,308

    Re: help needed

    const means that the data cannot be changed.

    Code:
    const unsigned char in[] = "qwerty";
    in contains the characters "qwerty" which cannot be changed.

    Code:
    unsigned char in[] = "qwerty";
    in again contains the characters "qwerty" but the characters in the array can be changed.

    Code:
    const unsigned char in[] = "qwerty";
    
    unsigned char in2[] = "qwerty";
    
    	in[0] = 'z';
    	in2[0] = 'z';
    In the above, the line highlighted produces a compile error as the code is trying to change the q to a z but in is defined as const so changes are not allowed. The in2 change is allowed as in2 is not defined as const.

    Hopes that helps.
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


Azure Activities Information Page

Windows Mobile Development Center


Click Here to Expand Forum to Full Width

This is a CodeGuru survey question.


Featured


HTML5 Development Center