Sample code for 30+ languages & platforms
Unicode C++

Attach a File with an Explicit Content Type

See more Email Object Examples

Demonstrates the Chilkat Email.AddFileAttachment2 method, which attaches a file from the filesystem and lets you explicitly specify its content type rather than having Chilkat infer it from the file extension. This example attaches a binary file as application/octet-stream.

Background: Extension-based type detection is convenient but not always right — a file may have an unusual or missing extension, or you may need a very specific MIME type for the recipient to process it correctly. Specifying the content type explicitly removes the guesswork. application/octet-stream is the generic "arbitrary binary data" type, a safe default that tells the client to treat the attachment as an opaque download rather than trying to render it.

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkEmailW.h>

void ChilkatSample(void)
    {
    bool success = false;

    //  Demonstrates the AddFileAttachment2 method, which attaches a file and lets you
    //  explicitly specify its content type instead of letting Chilkat infer it.

    CkEmailW email;
    email.put_Subject(L"Email with a file attachment");
    email.put_Body(L"Please see the attached file.");

    //  Attach a file, explicitly specifying the content type.
    success = email.AddFileAttachment2(L"qa_data/attachments/data.bin",L"application/octet-stream");
    if (success == false) {
        wprintf(L"%s\n",email.lastErrorText());
        return;
    }

    wprintf(L"NumAttachments = %d\n",email.get_NumAttachments());

    //  Note: The path "qa_data/attachments/data.bin" is a relative local filesystem path,
    //  relative to the current working directory of the running application.
    }