(MFC) Unzip an AES Encrypted Text File directly into a String Variable

A common need is to unzip from an AES encrypted Zip archive directly into a string variable, such that the unencrypted file never resides on disk, even temporarily. This example shows how to do it.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkZip.h>
#include <CkZipEntry.h>

void ChilkatSample(void)
    {
    CkString strOut;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkZip zip;

    // This example opens a WinZip-compatible AES encrypted
    // .zip that contains a single file: hamlet.xml.

    // It decrypts and unzips hamlet.xml directly into a string
    // variable.
    zip.SetPassword("secret");
    bool success = zip.OpenZip("qa_data/hamlet.zip");
    if (success != true) {
        strOut.append(zip.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    CkZipEntry *entry = zip.GetEntryByName("hamlet.xml");
    if (zip.get_LastMethodSuccess() == false) {
        strOut.append("Failed to find entry in zip");
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // lineEndingBehavior:
    // 0 = leave unchanged.
    // 1 = convert all to bare LF's
    // 2 = convert all to CRLF's
    int lineEndingBehavior = 0;
    const char *srcCharset = "utf-8";
    const char *xmlText = entry->unzipToString(lineEndingBehavior,srcCharset);
    strOut.append(xmlText);
    strOut.append("\r\n");
    delete entry;


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }