我如何使用iTextSharp的获得PDF文件部分目标页码？

有两种可能的链接注释，无论是 A 或目的地。在 A 是更强大的类型，但往往是矫枉过正。在目的地只输入指定一些配件和缩放选项以及间接引用的页面。

There's two possible types of Link Annotations, either A or Dest. The A is the more powerful type but is often overkill. The Dest type just specifies an indirect reference to a page along with some fitting and zooming options.

的目的地值可以是几个不同的事情，但通常是（据我所见过的）一个名为字符串目的地。你可以看一下命名目标文档的名称目的地字典。所以在你的主循环添加此，以便它可以在以后引用：

The Dest value can be a couple of different things but is usually (as far as I've ever seen) a named string destination. You can look up named destinations in the document's name destination dictionary. So before your main loop add this so that it can be referenced later:

//Get all existing named destinations
Dictionary<string, PdfObject> dests = pdfreader.GetNamedDestinationFromStrings();

一旦你得到了目的地作为一个字符串，你可以看看那个对象了在上述字典的关键。

Once you've got the Dest as a string you can look that object up as a key in the above dictionary.

PdfArray thisDest = (PdfArray)dests[AnnotationDictionary.GetAsString(PdfName.DEST).ToString()];

返回的数组中的第一项就是你用来间接引用。 （实际上，第一个项目可能会重新$ P $远程文档中psenting页数量的整数，所以你可能要检查这一点。）

The first item in the array returned is the indirect reference that you're used to. (Actually, the first item could be an integer representing a page number in a remote document so you might have to check for that.)

PdfIndirectReference a = (PdfIndirectReference)thisDest[0];
PdfObject thisPage = PdfReader.GetPdfObject(a);

下面是code，它把最上面的一起，去掉了一些code，你已经拥有的。 A 和目的地每所以没有标注应该永远都同时指定规范相互排斥的。

Below is code that puts most of the above together, omitting some of the code that you already have. A and Dest are mutually exclusive per the spec so no annotation should ever have both specified.

//Get all existing named desitnations
Dictionary<string, PdfObject> dests = pdfreader.GetNamedDestinationFromStrings();

foreach (PdfObject oAnnot in Annots.ArrayList) {
    PdfDictionary AnnotationDictionary = (PdfDictionary)PdfReader.GetPdfObject(oAnnot);

    if (AnnotationDictionary.Get(PdfName.SUBTYPE).Equals(PdfName.LINK)) {
        if (AnnotationDictionary.Contains(PdfName.A)) {
            //...Do normal A stuff here
        } else if (AnnotationDictionary.Contains(PdfName.DEST)) {
            if (AnnotationDictionary.Get(PdfName.DEST).IsString()) {//Named-based destination
                if (dests.ContainsKey(AnnotationDictionary.GetAsString(PdfName.DEST).ToString())) {//See if it exists in the global name dictionary
                    PdfArray thisDest = (PdfArray)dests[AnnotationDictionary.GetAsString(PdfName.DEST).ToString()];//Get the destination
                    PdfIndirectReference a = (PdfIndirectReference)thisDest[0];//TODO, this could actually be an integer for the case of Remote Destinations
                    PdfObject thisPage = PdfReader.GetPdfObject(a);//Get the actual PDF object
                }
            } else if(AnnotationDictionary.Get(PdfName.DEST).IsArray()) {
                //Technically possible, I think the array matches the code directly above but I don't have a sample PDF
            }
        }
    }
}