Unicode C

Get the Content-Location of a Related Item

Demonstrates the Chilkat Email.GetRelatedContentLocation method, which returns the Content-Location of a related item (typically an image or style sheet embedded within an HTML email). The index is zero-based. This example loads an image from a file into a BinData object and adds it as a related item addressed by Content-Location using AddRelatedBd2, then reads it back.

Background: Content-Location is the alternative to Content-ID for linking HTML to its embedded resources. Instead of a cid: reference, the HTML keeps an ordinary-looking src="logo.png", and the matching part carries a Content-Location of logo.png. Since the image is binary, it is loaded into a BinData object and added with AddRelatedBd2. This approach is common when an existing web page is turned into an email, since the original relative URLs can stay unchanged.

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Unicode C

#include <C_CkEmailW.h>
#include <C_CkBinDataW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmailW email;
    HCkBinDataW bdImage;
    const wchar_t *loc;

    success = FALSE;

    //  Demonstrates the GetRelatedContentLocation method, which returns the Content-Location of
    //  a related item.  Related items are typically images and style sheets embedded within
    //  HTML emails.  The index is zero-based.

    email = CkEmailW_Create();
    CkEmailW_putSubject(email,L"GetRelatedContentLocation example");

    //  The HTML references the image by the same name used as the Content-Location.
    CkEmailW_SetHtmlBody(email,L"<html><body><img src=\"logo.png\"/></body></html>");

    //  Load the image data from a file into a BinData object.
    bdImage = CkBinDataW_Create();
    success = CkBinDataW_LoadFile(bdImage,L"qa_data/images/logo.png");
    if (success == FALSE) {
        wprintf(L"%s\n",CkBinDataW_lastErrorText(bdImage));
        CkEmailW_Dispose(email);
        CkBinDataW_Dispose(bdImage);
        return true;
    }

    //  Add the image as a related item addressed by Content-Location "logo.png".
    success = CkEmailW_AddRelatedBd2(email,bdImage,L"logo.png");
    if (success == FALSE) {
        wprintf(L"%s\n",CkEmailW_lastErrorText(email));
        CkEmailW_Dispose(email);
        CkBinDataW_Dispose(bdImage);
        return true;
    }

    //  Read the Content-Location of the first related item (index 0).
    loc = CkEmailW_getRelatedContentLocation(email,0);
    wprintf(L"Related item 0 Content-Location: %s\n",loc);

    //  Note: The path "qa_data/images/logo.png" is a relative local filesystem path,
    //  relative to the current working directory of the running application.


    CkEmailW_Dispose(email);
    CkBinDataW_Dispose(bdImage);

    }