问在iOS应用程序中选择一个PDF页面

EN

 - (void)emailAction:(UIButton *)sender
{
    NSString *emailSubject = @"Subject";
    NSString *messageBody = @"message";

    MFMailComposeViewController *mc = [[MFMailComposeViewController alloc] init];
    mc.mailComposeDelegate = self;
    [mc setSubject:emailSubject];
    [mc setMessageBody:messageBody isHTML:NO];
    [mc addAttachmentData:[self getPage:sender.tag+1] mimeType:@"application/pdf" fileName:@"thePDF.pdf"];

    [self presentViewController:mc animated:YES completion:NULL];
}

- (NSMutableData *)getPage:(NSInteger)pageNumber
{
    CGPDFDocumentRef SourcePDFDocument = CGPDFDocumentCreateWithURL((CFURLRef)[NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"myPDF" ofType:@"pdf"]]); // Create the CGPDFDocument from the URL
    if (SourcePDFDocument == NULL) {
        return nil;
    }

    // Reference to Page current Page
    CGPDFPageRef SourcePDFPage = CGPDFDocumentGetPage(SourcePDFDocument, pageNumber);

    if (SourcePDFPage == NULL) {
        self.view.backgroundColor = [UIColor blueColor];
    }

    CGRect mediaBox = CGPDFPageGetBoxRect(SourcePDFPage, kCGPDFMediaBox);
    NSMutableData *outputData = [NSMutableData data];
    CGDataConsumerRef consumer = CGDataConsumerCreateWithCFData((__bridge CFMutableDataRef)outputData);
    CGContextRef context = CGPDFContextCreate(consumer, &mediaBox, NULL);
    // draw
    CGContextBeginPage(context, &mediaBox);
    CGContextDrawPDFPage(context, SourcePDFPage);
    CGContextEndPage(context);
    // cleanup
    CGDataConsumerRelease(consumer);
    CGContextRelease(context);

    return outputData;
}