以下代码来自微软提供的“[direct 2 DAP 打印示例(Windows 8.1)](http://code.msdn.microsoft.com/windowsapps/Direct2Dapp-printing-sample-9869f99C# content) ”。我已经修改了格式，以更好地适应这本书的页面；这导致了更难阅读的代码。为了方便起见，此处包含了这段代码，原始代码(可以与微软 Windows 8 示例一起下载)可读性更强。所有评论都是微软的。我只修改了上面提到的格式。它们指的是从中下载代码的示例。
微软提供的示例代码中的类名是 D2DPageRenderer。对于我们的打印应用程序，这应该改为“简单文本渲染器”。我在后面的代码中用绿色突出显示了这一行。我们代码中的主渲染器类被称为 SimpleTextRenderer，因此您还必须将对 PageRenderer 类的所有引用都更改为 SimpleTextRenderer。我用红色突出了这些线条。
DocSource.h 列表
//// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
//// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
//// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
//// PARTICULAR PURPOSE.
////
//// Copyright (c) Microsoft Corporation. All rights reserved
#pragma once
#include <windows.graphics.printing.h>
#include <printpreview.h>
#include <documentsource.h>
#include "D2DPageRenderer.h"
类 CDocumentSource:public Microsoft::WRL::RuntimeClass<:wrl::runtimeclassflags>，
ABI::Windows::Graphics::Printing::IPrintDocumentSource，
IPrintDocumentPageSource，
IPrintPreviewPageCollection >
{
私人:
可检查类(L”窗口。图形. Printing.IPrintDocumentSource "，
baseTrust)；
公共:
HRESULT RuntimeClassInitialize(
_ In _ Iunknown * page renderer){ 0
HRESULT hr = (pageRenderer！=空值？S_OK : E_INVALIDARG：
if(SUCCESS(HR)){ 0
m _ paginateCalled = false
m_totalPages = 1：
m _ height = 0.f
m _ width = 0.f
//将 d2dRender 强制转换回 PageRenderer 对象。
m _ renderer = re interpret _ cast(page renderer)；
}
返回 HR；
}
//
//经典的 COM 接口 IDocumentPageSource 方法
//
IFACEMETHODIMP
GetPreviewPageCollection(
_ in _ iprindocumentpackage target * docpackage target，
_ out _ ipprintpreviewpagecollection * * docpagecollection
);
IFACEMETHODIMP
MakeDocument(
_ In _ IInspectable *文档选项，
_ in _ ipprintdocumentpacktarget * docpackage target
);
//
//经典的 COM 接口 IPrintPreviewPageCollection 方法
//
IFACEMETHODIMP
分页(
_ In _ uint32 currentJobPage，
_ In _ iinspective * docOptions)；
IFACEMETHODIMP
MakePage(
S7-1200 可编程控制器，
In float 宽度，
In float 高度)；
私人:
浮点转换页面大小(
In float desiredWidth，
In float desiredHeight，
_ Out _ Windows::Foundation::Size * previewSize)；
uint32 m_totalPages：
bool m _ paginateCalled
float m _ height
float m _ width
D2D1_RECT_F m_imageableRect;
pagerenderer^ m _ renderer；
Microsoft::wrl::comptrm _ dxgipreviewtarget；
};
DocSource.cpp 列表
//// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
//// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
//// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
//// PARTICULAR PURPOSE.
////
//// Copyright (c) Microsoft Corporation. All rights reserved
#include "pch.h"
#include "docsource.h"
using namespace Microsoft::WRL;
using namespace Windows::Graphics::Printing;
#pragma region IDocumentPageSource Methods
IFACEMETHODIMP
CDocumentSource::GetPreviewPageCollection(
_In_ IPrintDocumentPackageTarget* docPackageTarget,
_Out_ IPrintPreviewPageCollection** docPageCollection
)
{
HRESULT hr = (docPackageTarget != nullptr) ? S_OK : E_INVALIDARG;
// Get for IPrintPreviewDxgiPackageTarget interface.
if (SUCCEEDED(hr)){
hr = docPackageTarget->GetPackageTarget(
ID_PREVIEWPACKAGETARGET_DXGI,
IID_PPV_ARGS(&m_dxgiPreviewTarget));
}
ComPtr<IPrintPreviewPageCollection> pageCollection;
if (SUCCEEDED(hr)){
ComPtr<CDocumentSource> docSource(this);
hr = docSource.As<IPrintPreviewPageCollection>(&pageCollection);
}
if (SUCCEEDED(hr)){
hr = pageCollection.CopyTo(docPageCollection);
}
return hr;
}
IFACEMETHODIMP
CDocumentSource::MakeDocument(
_In_ IInspectable* docOptions,
_In_ IPrintDocumentPackageTarget* docPackageTarget)
{
if (docOptions == nullptr || docPackageTarget == nullptr){
return E_INVALIDARG;
}
// Get print settings from PrintTaskOptions for printing,
// such as page description,
// which contains page size, imageable area, DPI.
// User can obtain other print settings in the same way, such as ColorMode,
// NumberOfCopies, etc., which are not shown in this sample.
PrintTaskOptions^ option = reinterpret_cast<PrintTaskOptions^>(docOptions);
// Get the description of the first page.
PrintPageDescription pageDesc = option->GetPageDescription(1);
// Create a print control properties and set DPI from PrintPageDescription.
D2D1_PRINT_CONTROL_PROPERTIES printControlProperties;
// DPI for rasterization of all unsupported D2D commands or options
printControlProperties.rasterDPI = (float)(min(pageDesc.DpiX,
pageDesc.DpiY));
// Color space for vector graphics in D2D print control.
printControlProperties.colorSpace = D2D1_COLOR_SPACE_SRGB;
// Subset for used glyphs, send and discard font resource after every
// five pages
printControlProperties.fontSubset = D2D1_PRINT_FONT_SUBSET_MODE_DEFAULT;
HRESULT hr = S_OK;
try {
// Create a new print control linked to the package target.
m_renderer->CreatePrintControl(docPackageTarget,&printControlProperties);
// Calculate imageable area and page size from PrintPageDescription.
D2D1_RECT_F imageableRect = D2D1::RectF(
pageDesc.ImageableRect.X, pageDesc.ImageableRect.Y,
pageDesc.ImageableRect.X + pageDesc.ImageableRect.Width,
pageDesc.ImageableRect.Y + pageDesc.ImageableRect.Height
);
D2D1_SIZE_F pageSize = D2D1::SizeF(pageDesc.PageSize.Width,
pageDesc.PageSize.Height);
// Loop to add page command list to d2d print control.
for (uint32 pageNum = 1; pageNum <= m_totalPages; ++pageNum){
m_renderer->PrintPage(pageNum, imageableRect, pageSize,
nullptr // If a page-level print ticket is not specified here, the
//package print ticket is applied for each page.
);
}
}
catch (Platform::Exception^ e){
hr = e->HResult;
if (hr == D2DERR_RECREATE_TARGET){
// In case of device lost, the whole print job will be aborted,
// and we should recover
// so that the device is ready when used again. At the same time,
// we should propagate this error to the Modern Print Dialog.
m_renderer->HandleDeviceLost();
}
}
// Make sure to close d2d print control even if AddPage fails.
HRESULT hrClose = m_renderer->ClosePrintControl();
if (SUCCEEDED(hr)){
hr = hrClose;
}
return hr;
}
#pragma endregion IDocumentPageSource Methods
#pragma region IPrintPreviewPageCollection Methods
IFACEMETHODIMP CDocumentSource::Paginate(
_In_ uint32 currentJobPage,
_In_ IInspectable* docOptions
)
{
HRESULT hr = (docOptions != nullptr) ? S_OK : E_INVALIDARG;
if (SUCCEEDED(hr)) {
// Get print settings from PrintTaskOptions for preview, such as page
// description, which contains page size, imageable area, DPI.
// User can obtain other print settings in the same way, such
// as ColorMode,
// NumberOfCopies, etc., which are not shown in this sample.
PrintTaskOptions^ option =
reinterpret_cast<PrintTaskOptions^>(docOptions);
PrintPageDescription pageDesc =
option->GetPageDescription(currentJobPage);
hr = m_dxgiPreviewTarget->InvalidatePreview();
// Set the total page number.
if (SUCCEEDED(hr)){
hr = m_dxgiPreviewTarget->SetJobPageCount(
PageCountType::FinalPageCount, m_totalPages);
}
if (SUCCEEDED(hr)) {
m_width = pageDesc.PageSize.Width;
m_height = pageDesc.PageSize.Height;
m_imageableRect = D2D1::RectF(
pageDesc.ImageableRect.X,
pageDesc.ImageableRect.Y,
pageDesc.ImageableRect.X + pageDesc.ImageableRect.Width,
pageDesc.ImageableRect.Y + pageDesc.ImageableRect.Height
);
// Now we are ready to let MakePage to be called.
m_paginateCalled = true;
}
}
return hr;
}
// Here, desiredWidth/desiredHeight is the desired size of preview surface
// by print mananger in system. The final size of the preview surface must
// have the same proportion as that of the desired width/height.
// In this sample, we just use it as preview size and return the scale variant
// for surface drawing.
// The size here is in DIPs.
Float CDocumentSource::TransformedPageSize(
_In_ float desiredWidth,
_In_ float desiredHeight,
_Out_ Windows::Foundation::Size* previewSize
){
float scale = 1.0f;
if (desiredWidth > 0 && desiredHeight > 0) {
previewSize->Width = desiredWidth;
previewSize->Height = desiredHeight;
scale = m_width / desiredWidth;
}
else {
previewSize->Width = 0;
previewSize->Height = 0;
}
return scale;
}
// This sample only acts upon orientation setting for an example.
// The orientation is read from the user selection in the Print Experience
// and is then used to reflow the content in a different way.
IFACEMETHODIMP CDocumentSource::MakePage(
_In_ uint32 desiredJobPage,
_In_ float width,
_In_ float height){
HRESULT hr = (width > 0 && height > 0) ? S_OK : E_INVALIDARG;
// When desiredJobPage is JOB_PAGE_APPLICATION_DEFINED, it means a new
// preview begins. If the implementation here is by an async way,
// for example, queue MakePage calls for preview, app needs to clean
// resources for previous preview before next.
// In this sample, we will reset page number if Paginate() has been called.
if (desiredJobPage == JOB_PAGE_APPLICATION_DEFINED && m_paginateCalled){
desiredJobPage = 1;
}
if (SUCCEEDED(hr) && m_paginateCalled){
// Calculate the size of preview surface, according to desired width and
// height.
Windows::Foundation::Size previewSize;
float scale = TransformedPageSize(width, height, &previewSize);
try {
m_renderer->DrawPreviewSurface(
previewSize.Width, previewSize.Height, scale, m_imageableRect,
desiredJobPage,m_dxgiPreviewTarget.Get());
}
catch (Platform::Exception^ e) {
hr = e->HResult;
if (hr == D2DERR_RECREATE_TARGET){
// In case of device lost, we should recover so that the device is
// ready to render the next preview page when requested. At the same time,
// we should propagate this error to the Modern Print Dialog.
m_renderer->HandleDeviceLost();
}
}
}
return hr;
}
#pragma region IPrintPreviewPageCollection Methods