C++

File Read Blocks

Demonstrates how to read a file in fixed-size blocks (except for the very last block). C++

#include <CkByteData.h>
#include <CkFileAccess.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Demonstrates how to read a file in blocks,
    //  which can be useful when uploading to cloud storage
    //  services such as Azure, S3, Google, etc.

    //  For this example, we're simply writing the blocks
    //  to an output file, and then checking to see if the
    //  resulting file contents equals the original file contents.

    CkByteData dataBlock;

    CkFileAccess facSrc;
    CkFileAccess facDest;

    const char *srcPath = "qa_data/xml/hamlet.xml";
    const char *destPath = "qa_output/hamletOut.xml";

    success = facSrc.OpenForRead(srcPath);
    success = facDest.OpenForWrite(destPath);
    //  Assuming success for the example..

    //  How many 1024-byte blocks?  (Including 1 for the last partial block)
    int numBlocks = facSrc.GetNumBlocks(1024);

    int i = 0;
    while ((i < numBlocks)) {
        success = facSrc.ReadBlock(i,1024,dataBlock);
        if (facSrc.get_LastMethodSuccess() != true) {
            std::cout << facSrc.lastErrorText() << "\r\n";
            return;
        }

        success = facDest.FileWrite(dataBlock);
        if (success != true) {
            std::cout << facDest.lastErrorText() << "\r\n";
            return;
        }

        i = i + 1;
    }

    facSrc.FileClose();
    facDest.FileClose();

    bool bEqual = facSrc.FileContentsEqual(srcPath,destPath);
    if (bEqual != true) {
        std::cout << "Something went wrong!" << "\r\n";
        return;
    }

    std::cout << "File successfully copied by blocks." << "\r\n";
    }