PDF Core Layer

Revision as of 13:57, 7 September 2015

Introduction

PDF Core Library is one layer of the PDF-XChange Editor SDK and PDF-XChange Core PDF SDK. Interfaces of this layer provide access to high level objects of a PDF file, such as document, pages, annotations, form fields, etc.

The creation of new documents as well as modification to existing documents is supported. Further a means to render PDF pages to devices or to image to display content to a users screen is available.

PDF-XChange Core SDK

If the PDF-XChange Core PDF SDK is used, it must be initialized calling IPXC_Inst::Init method and should be finalized by calling the IPXC_Inst::Finalize method. This method will have no effect within the PDF-XChange Editor SDK.

The PDF-XChange Core SDK consists of one DLL and can be used without registration as a COM server. To use the PDF-XChange Core SDK a developer must create an instance of the IPXC_Inst object. There are several ways to do this.

• If the PDF-XChange Core SDK is used as a registered COM server, an IPXC_Inst object should be created using CoCreateInstance call:

HRESULT fGetInst(CComPtr<IPXC_Inst>& inst)
{
  inst = nullptr;
  HRESULT hr = CoCreateInstance(__uuidof(PXC_Inst), nullptr, CLSCTX_INPROC_SERVER, __uuidof(IPXC_Inst), (void**)&inst);
  return hr;
}

• If using the PDF-XChange Core SDK without registration as a COM server, the function PXC_GetInstance, exported by the SDK's DLL should be called to get the IPXC_Inst object:

typedef HRESULT (WINAPI *fnPXC_GetInstance)(IPXC_Inst** ppInst);

HRESULT fGetInst(CComPtr<IPXC_Inst>& inst)
{
  inst = nullptr;
  HMODULE hSDKInst = LoadLibrary(_T("PDFXCoreAPI.x64.dll"));
  if (hSDKInst == nullptr)
    return E_FAIL;
  fnPXC_GetInstance pfn = (fnPXC_GetInstance)GetProcAddress(hSDKInst, "PXC_GetInstance");
  if (pfn == nullptr)
    return E_FAIL;
  HRESULT hr = pfn(&inst);
  return hr;
}

When IPXC_Inst is received, its method Init must be called to initialize the SDK and pass optionally a valid serial key. Use without first making this call with a valid serial key will result in the SDK functioning in 'Evaluation' mode.

PDF-XChange Editor SDK

In the PDF-XChange Editor SDK the IPXC_Inst is initialized by the SDK itself and the methods Init and Finalize should not be used. IPXC_Inst object can be retrieved from the PDF-XChange Editor SDK's main object in the following way:

HRESULT fGetInst(IPXV_Inst* pVInst, CComPtr<IPXC_Inst>& inst)
{
  inst = nullptr;
  if (pVInst == nullptr)
    return E_INVALIDARG;
  CComPtr<IUnknown> pExt;
  HRESULT hr = pVInst->GetExtension(L"PXC", &pExt);
  if (FAILED(hr))
    return hr;
  hr = pExt->QueryInterface<IPXC_Inst>(&inst);
  return hr;
}

References

• Enumerations
• Interfaces
• Structures