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C++

Convert ASN.1 to/from Binary DER, XML, and Base64

Demonstrates how to convert ASN.1 from and to any of the following formats: binary DER, Base64, and XML.

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C++
#include <CkAsn.h>
#include <CkXml.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkAsn asn;

    //  Begin with loading ASN.1 from a binary DER/BER format file.
    success = asn.LoadBinaryFile("/Users/chilkat/testData/p7b/test.p7b");
    if (success != true) {
        std::cout << asn.lastErrorText() << "\r\n";
        return;
    }

    //  Convert ASN.1 to XML:
    const char *strXml = asn.asnToXml();
    if (asn.get_LastMethodSuccess() != true) {
        std::cout << asn.lastErrorText() << "\r\n";
        return;
    }

    //  The XML returned by AsnToXml will be compact and not pretty-formatted.
    //  Use Chilkat XML to format the XML better:
    CkXml xml;
    success = xml.LoadXml(strXml);
    //  Assuming success for this example..
    //  This is formatted better for human viewing:
    std::cout << xml.getXml() << "\r\n";

    //  Now get the ASN.1 in base64 format.  Any encoding supported
    //  by Chilkat can be passed, such as "hex", "uu", "quoted-printable", "base32", "modbase64", etc.
    const char *strBase64 = asn.getEncodedDer("base64");

    //  Load the ASN.1 from XML:
    CkAsn asn2;
    success = asn2.LoadAsnXml(xml.getXml());
    if (success != true) {
        std::cout << asn2.lastErrorText() << "\r\n";
        return;
    }

    //  Load the ASN.1 from an encoded string, such as base64:
    CkAsn asn3;
    success = asn3.LoadEncoded(strBase64,"base64");
    if (success != true) {
        std::cout << asn3.lastErrorText() << "\r\n";
        return;
    }
    }