任何人都可以帮助我使用IOS读写PDF中的注释

问题描述

|| 谁能帮助我使用iOS在PDF中阅读和编写注释吗？这是我尝试过的示例代码。谁能告诉我我要去哪里错了？我可以加载注释数组，但是当我尝试获取A的字典（下面的行）时，我无法解析它。

CGPDFDictionaryRef aDict;
        if(!CGPDFDictionaryGetDictionary(annotDict,\"A\",&aDict)) 

我尝试过的代码如下：

CGpdfpageRef pageAd = CGPDFDocumentGetPage(pdf,index+1);

CGPDFDictionaryRef pageDictionary = CGpdfpageGetDictionary(pageAd);

CGPDFArrayRef outputArray;
if(!CGPDFDictionaryGetArray(pageDictionary,\"Annots\",&outputArray)) {
    return;
}

int arrayCount = CGPDFArrayGetCount( outputArray );


for( int j = 0; j < arrayCount; ++j ) {
    CGPDFObjectRef aDictObj;
    if(!CGPDFArrayGetobject(outputArray,j,&aDictObj)) {
        return;
    }

    CGPDFDictionaryRef annotDict;
    if(!CGPDFObjectGetValue(aDictObj,kCGPDFObjectTypeDictionary,&annotDict)) {
        return;
    }

    CGPDFDictionaryRef aDict;
    if(!CGPDFDictionaryGetDictionary(annotDict,&aDict)) {
        return;
    }

    CGPDFStringRef uriStringRef;
    if(!CGPDFDictionaryGetString(aDict,\"URI\",&uriStringRef)) {
        return;
    }

    CGPDFArrayRef rectArray;
    if(!CGPDFDictionaryGetArray(annotDict,\"Rect\",&rectArray)) {
        return;
    }

    int arrayCount = CGPDFArrayGetCount( rectArray );
    CGPDFReal coords[4];
    for( int k = 0; k < arrayCount; ++k ) {
        CGPDFObjectRef rectObj;
        if(!CGPDFArrayGetobject(rectArray,k,&rectObj)) {
            return;
        }

        CGPDFReal coord;
        if(!CGPDFObjectGetValue(rectObj,kCGPDFObjectTypeReal,&coord)) {
            return;
        }

        coords[k] = coord;
    }               

    char *uriString = (char *)CGPDFStringGetBytePtr(uriStringRef);

    Nsstring *uri = [Nsstring stringWithCString:uriString encoding:NSUTF8StringEncoding];
    CGRect rect = CGRectMake(coords[0],coords[1],coords[2],coords[3]);

    CGPDFInteger pageRotate = 0;
    CGPDFDictionaryGetInteger( pageDictionary,\"Rotate\",&pageRotate ); 
    CGRect pageRect = CGRectIntegral( CGpdfpageGetBoxRect( page,kCGPDFMediaBox ));
    if( pageRotate == 90 || pageRotate == 270 ) {
        CGFloat temp = pageRect.size.width;
        pageRect.size.width = pageRect.size.height;
        pageRect.size.height = temp;
    }

    rect.size.width -= rect.origin.x;
    rect.size.height -= rect.origin.y;

    CGAffineTransform trans = CGAffineTransformIdentity;
    trans = CGAffineTransformTranslate(trans,pageRect.size.height);
    trans = CGAffineTransformScale(trans,1.0,-1.0);

    rect = CGRectApplyAffineTransform(rect,trans);

    // do whatever you need with the coordinates.
    // e.g. you Could create a button and put it on top of your page
    // and use it to open the URL with UIApplication\'s openURL
    NSURL *url = [NSURL URLWithString:uri];
    NSLog(@\"URL: %@\",url);
    //          CGPDFContextSetURLForRect(ctx,(CFURLRef)url,rect);
    UIButton *button = [[UIButton alloc] initWithFrame:rect];
    [button setTitle:@\"LINK\" forState:UIControlStatenormal];
    [button addTarget:self action:@selector(openLink:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];

解决方法

在注释字典中，A键是可选的。如果注释是指向另一个页面的链接，则它可能使用Dest键。或者它可能在其他操作字典中使用U键。如果无法检索A词典，请尝试加载AA密钥。如果它不存在，则注释不具有操作。如果存在，则从AA字典中加载U键。