Salesforce Apex实现双PDF合并并关联自定义对象及邮件发送技术问询

Hey there, let's walk through a proper solution for your requirement. First up, the approach you initially tried—just concatenating the hex strings of the two PDFs—won't work because PDFs have a specific file structure. Merging them that way will create a corrupted file that can't be opened. Instead, we'll use Salesforce's built-in PDFMerger class (available in API version 48.0 and later) to combine the PDFs correctly.

Here's the complete, working Apex code with explanations:

public static void mergePdfAndSend(Id customObjectRecordId) {
    // Step 1: Generate PDF blobs from your Visualforce pages
    PageReference firstPdfPage = new PageReference('/apex/FirstPDF?id=' + customObjectRecordId);
    Blob firstPdfBlob = firstPdfPage.getContentAsPDF(); // Prefer getContentAsPDF for reliable PDF output
    
    PageReference secondPdfPage = new PageReference('/apex/SecondPDF?id=' + customObjectRecordId);
    Blob secondPdfBlob = secondPdfPage.getContentAsPDF();

    // Step 2: Merge the PDFs properly with PDFMerger
    PDFMerger pdfMerger = new PDFMerger();
    pdfMerger.addDocument(firstPdfBlob);
    pdfMerger.addDocument(secondPdfBlob);
    Blob mergedPdf = pdfMerger.merge();

    // Step 3: Create and attach the merged PDF to your custom object
    Attachment pdfAttachment = new Attachment();
    pdfAttachment.Body = mergedPdf;
    pdfAttachment.Name = 'Combined_Document_' + DateTime.now().format('yyyyMMddHHmm') + '.pdf'; // Unique name to avoid conflicts
    pdfAttachment.ParentId = customObjectRecordId; // Link to your custom object record
    pdfAttachment.ContentType = 'application/pdf'; // Critical for correct file recognition
    try {
        insert pdfAttachment;
        System.debug('Merged PDF attached successfully: ' + pdfAttachment.Id);
    } catch(DmlException e) {
        System.debug('Error attaching PDF: ' + e.getMessage());
        throw new AuraHandledException('Failed to save merged PDF: ' + e.getMessage());
    }

    // Step 4: Send the merged PDF via email
    Messaging.SingleEmailMessage email = new Messaging.SingleEmailMessage();
    email.setToAddresses(new String[] {'recipient@example.com'}); // Replace with actual recipient email(s)
    email.setSubject('Your Combined PDF Document');
    email.setPlainTextBody('Hi there,\n\nPlease find your merged PDF document attached.\n\nThanks,\nYour Team');

    // Prepare the email attachment
    Messaging.EmailFileAttachment emailAttachment = new Messaging.EmailFileAttachment();
    emailAttachment.setFileName(pdfAttachment.Name);
    emailAttachment.setBody(mergedPdf);
    emailAttachment.setContentType('application/pdf');
    email.setFileAttachments(new Messaging.EmailFileAttachment[] {emailAttachment});

    try {
        Messaging.SendEmailResult[] results = Messaging.sendEmail(new Messaging.SingleEmailMessage[] {email});
        if(results[0].isSuccess()) {
            System.debug('Email sent successfully');
        } else {
            String errorMsg = results[0].getErrors()[0].getMessage();
            System.debug('Failed to send email: ' + errorMsg);
            throw new AuraHandledException('Error sending email: ' + errorMsg);
        }
    } catch(Exception e) {
        System.debug('Unexpected error sending email: ' + e.getMessage());
        throw new AuraHandledException('Failed to send email: ' + e.getMessage());
    }
}

Key Notes & Best Practices: #

• PDF Generation: Use getContentAsPDF() instead of getContent() to ensure you get a valid PDF blob—getContent() might return HTML if your Visualforce page has rendering issues. Also, make sure your VF pages include <apex:page renderAs="pdf"> at the top to enforce PDF rendering.
• Proper Merging: The PDFMerger class handles the underlying PDF structure, so your merged file will be fully functional. If you're stuck on an older API version without PDFMerger, you'd need to use a third-party PDF parsing library, but PDFMerger is the supported, recommended approach now.
• Attachment Naming: Adding a timestamp to the attachment name helps avoid overwriting existing files if you run this process multiple times for the same record.
• Permissions: Ensure the user executing this Apex has access to both Visualforce pages, the custom object, and has the "Send Email" permission in their profile.
• Email Limits: Keep Salesforce's daily email limits in mind if you're running this for multiple records.

内容的提问来源于stack exchange，提问作者Veerpal