PDF Core Layer
Introduction
PDF Core Library is one layer of the PDF-XChange Editor SDK and PDF-XChange Core API 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 API SDK
If the PDF-XChange Core API 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 API SDK consists of one DLL and can be used without registration as a COM server. To use the PDF-XChange Core API SDK a developer must create an instance of the IPXC_Inst object. There are several ways to do this.
- If the PDF-XChange Core API 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 API 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; }