Use this method to read a PDF into a document object. Any
existing document content will be discarded.
You can specify the PDF as a file path or by passing in the raw
PDF data. Raw data must be held as an array of bytes. You can open
encrypted PDF documents if you supply a valid password.
After the read operation is complete, the Page property will contain the ID of
the first page in the document. The Rect and MediaBox properties will reflect
the size of the first page in the document.
ABCpdf operates an intelligent just-in-time object loading
scheme, which ensures that only those objects that are required are
loaded into memory. This means that if you are modifying large
documents, then server load will be kept to a minimum. The original
PDF document must be available for as long as the Document object
is being used.
As a result, you cannot overwrite a PDF file while it is open
for reading. You will need to save your PDF to another location and
then swap the two files round.
Object deletion requires that all references to an object be
removed. There is no way of doing this without checking each object
in the document. So object deletion requires that every object in
the document is loaded, and for large documents, this may place a
significant load on the server.
Reading encrypted documents places a greater load on the server
because - like object deletion - it requires that every object in
the document be loaded.
Please note that you are legally bound to respect the
permissions present in existing PDF documents. For details, please
see the Legal Requirement
The Read method may be used to read eForm FDF documents as well
as PDF documents. Most PDF operations will not work on FDF
documents, but you can query field values using the GetInfo methods
to return Unicode strings.
Modifying Documents. ABCpdf will allow you to open,
modify and save PDF documents.
ABCpdf will allow you to draw on top of PDF documents or add or
delete pages or modify document data. However, because of the way
that PDF documents are structured, it's unlikely that you'll be
able to edit existing content.
So if there are blank spaces which you can draw your entries
into, that will work. Indeed, you might want to draw a white box
over existing content and then draw on that.
However, you shouldn't expect to be able to edit and re-flow
text that is already in your PDF.