question about casting pointers/other types also??

This is a discussion on question about casting pointers/other types also?? within the C++ Programming forums, part of the General Programming Boards category; Hi, I have been trying to figure out casting, and have a quick question I hope someone can help me ...

  1. #1
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    question about casting pointers/other types also??

    Hi,

    I have been trying to figure out casting, and have a quick question I hope someone can help me with:

    What exactly is the purpose of casting, like for int, char...etc...:
    example:
    int x = 5;
    (char) x;

    I am confused about this? what does it mean, and why is it needed??


    Also, I keep seeing code where it mentions casting a pointer:
    example:
    (void *) something;

    Could someone please explain what casting a pointer means and why it is needed??

    Thanks a lot for any explanation! It is appreciated!

  2. #2
    Hardware Engineer
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    First, typecasting isn't used that often.

    It is used when a number passed to a function is different from what the function requires. If your function expects an int, and you only have a char, you need to cast the char to an int.

    This shouldn't happen if you wrote the program and the function yourself, but it could happen if you are using a library function.

    A void pointer is a pointer that can point to any type. There's some info from a tutorial at cplusplus.com (Look for "void pointers" near the bottom of the page.)

  3. #3
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    thanks

    Thank you, it makes much more sense now , thanks a lot!

  4. #4
    Registered User The Dog's Avatar
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    >> First, typecasting isn't used that often.

    Perhaps with simple data types, but typecasting is almost always used in almost every C++ program where classes or templates are used.

    It is important to understand how C++ typecasting works.

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