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Thread: QByteArray

  1. #1
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    Question QByteArray

    Hi all!

    I created QByteArray dynamically- QByteArray(NULL, BUFFER_SIZE) I want it to do this:
    I want "N" bytes of some "DATA" to be copied to this QByteArray. So something like memcpy function does. Is there any method like this ? I was lookig for it but no success I can do that in for cycle but that's not good
    Is there any other function I could use for doing this ?
    Thanks

  2. #2
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    Default Re: QByteArray

    See QByteArray::append(const char*) or QByteArray::data ( the non-const version).
    With the latter you could use memcpy, but you'll have to allocate it first( I think, it is not tested). The first one is safer, just appends the buffer.

  3. #3
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    Default Re: QByteArray

    See QByteArray::data() for a pointer to the data buffer and QBuffer for a QIODevice interface to the byte array. You can use either way to fill the byte array.

  4. #4
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    Question Re: QByteArray

    Well, Wysota's ideas are very close to what I want.
    The thing is that I already have data in my own data buffer:

    const char* data.

    and I want only : int buffer_size number of these data to be copied to my
    QByteArray

    data() return a pointer to the data stored in QByteArray that I know.
    BUT how to COPY data into it ?? Append add all data in buffer...I need only "buffer_size" bytes.
    Thanks

  5. #5
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    Default Re: QByteArray

    Oh, then you might want to try:
    QByteArray::QByteArray ( const char * data, int size )
    Constructs a byte array containing the first size bytes of array data.
    If data is 0, a null byte array is constructed.
    QByteArray makes a deep copy of the string data.
    But this way you can only copy the first size bytes.

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