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C++

Extract data:image/png;base64 from HTML

See more Base64 Examples

Demonstrates how to extract base64 image data from HTMl and save to files.

Chilkat C++ Downloads

C++
#include <CkStringBuilder.h>
#include <CkBinData.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkStringBuilder sb;
    CkBinData bd;
    CkStringBuilder sbFilename;
    int index = 1;

    success = sb.LoadFile("qa_data/html/oresp body.txt","utf-8");
    // Assume success.
    std::cout << "length = " << sb.get_Length() << "\r\n";

    bool mayHaveMore = true;
    while (mayHaveMore == true) {

        // Get the base64 between the 1st occurrence "data:image/png;base64," and "'"
        const char *sBase64 = sb.getBetween("data:image/png;base64,","'");

        // If nothing is found, then we'll exit the loop because there are no more.
        mayHaveMore = sb.get_LastMethodSuccess();

        if (sb.get_LastMethodSuccess() == true) {
            // Found something.
            // Load into bd and save.
            success = bd.LoadEncoded(sBase64,"base64");

            sbFilename.SetString("qa_output/png_");
            sbFilename.AppendInt(index);
            sbFilename.Append(".png");

            bd.WriteFile(sbFilename.getAsString());

            // Replace "data:image/png;base64" with "data:image-png;base64" so the next iteration finds the next occurrence.
            sb.ReplaceFirst("data:image/png;base64","data:image-png;base64");
        }

        index = index + 1;
    }

    // Restore our replacements..
    int count = sb.Replace("data:image-png;base64","data:image/png;base64");

    std::cout << "All done." << "\r\n";
    }