private MemoryStream GetStream(CAcroPDPage page, double resolution)
{
MemoryStream ms = new MemoryStream();
Thread th = new Thread(new ThreadStart(delegate()
{
/* 以下剪贴板操作仅在wpf下工作 */
// Render to clipboard, scaled by 100 percent (ie. original size)
// Even though we want a smaller image, better for us to scale in .NET
// than Acrobat as it would greek out small text
page.CopyToClipboard(_rect, 0, 0, (short)(100 * resolution));
var clipboardData = Clipboard.GetDataObject();
if (clipboardData.GetDataPresent(DataFormats.Bitmap))
{
var source = (InteropBitmap)clipboardData.GetData(DataFormats.Bitmap);
BmpBitmapEncoder encoder = new BmpBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(source));
encoder.Save(ms);
}
}));
th.TrySetApartmentState(ApartmentState.STA);
th.Start();
th.Join();
return(ms);
}
private void ExportAsImage(string strFile, string strExportPath)
{
if (!Directory.Exists(strExportPath))
{
Directory.CreateDirectory(strExportPath);
}
Acrobat.AcroPDDoc pdf = new AcroPDDoc();
pdf.Open(strFile);
int pageCount = Convert.ToInt32(txtPage.Text);
int count = pdf.GetNumPages();
for (int i = 0; i < count; i++)
{
if (i == pageCount)
{
break;
}
listMsg.Items.Add($"正在导出第{i + 1}页(共{count}页)");
listMsg.TopIndex = listMsg.Items.Count - 1;
int zoom = 1;
while (true)
{
try
{
CAcroPDPage page = (CAcroPDPage)pdf.AcquirePage(i);
CAcroRect pdfRect = (Acrobat.CAcroRect)Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.Rect", "");
CAcroPoint pdfPoint = (Acrobat.CAcroPoint)page.GetSize();
int imgWidth = (int)((double)pdfPoint.x * zoom);
int imgHeight = (int)((double)pdfPoint.y * zoom);
//设置裁剪矩形的大小为当前页的大小
pdfRect.Left = 0;
pdfRect.right = (short)imgWidth;
pdfRect.Top = 0;
pdfRect.bottom = (short)imgHeight;
page.CopyToClipboard(pdfRect, 0, 0, (short)(100 * zoom));
Object obj = Clipboard.GetData(DataFormats.Bitmap);
using (Bitmap bitmap = (Bitmap)obj)
{
SavePicture(bitmap, strExportPath, Path.GetFileNameWithoutExtension(strFile), (i + 1).ToString());
}
}
catch (Exception e)
{
continue;
}
break;
}
}
}
private void ExportAsImages(string fileName, string filePath)
{
try
{
CAcroPDDoc acroPDDoc = new AcroPDDocClass();
if (!acroPDDoc.Open(filePath))
{
Marshal.ReleaseComObject(acroPDDoc);
acroPDDoc = null;
throw new ApplicationException("Can't open file \"" +
fileName + "\"");
}
int pageCount = acroPDDoc.GetNumPages();
if (pageCount == 2)
{
CAcroPDPage acroPDPage = (CAcroPDPage)acroPDDoc.AcquirePage(1);
CAcroPoint acroPoint = (CAcroPoint)acroPDPage.GetSize();
CAcroRect acroRect = new AcroRectClass();
acroRect.Top = 0;
acroRect.bottom = acroPoint.y;
acroRect.Left = 0;
acroRect.right = acroPoint.x;
if (!acroPDPage.CopyToClipboard(acroRect, 0, 0, 100))
{
Marshal.ReleaseComObject(acroPDPage);
acroPDPage = null;
Marshal.ReleaseComObject(acroPDDoc);
acroPDDoc = null;
throw new ApplicationException("Unknown error while extracting pages of " + filePath);
}
acroRect = null;
acroPoint = null;
Marshal.ReleaseComObject(acroPDPage);
acroPDPage = null;
IDataObject dataObject = Clipboard.GetDataObject();
Bitmap bitmap = (Bitmap)dataObject.GetData(DataFormats.Bitmap);
string newFileName =
fileName.Substring(0, fileName.LastIndexOf(".")) + "_Page2.jpg";
string targetPath = rootPath + "\\" + newFileName;
if (File.Exists(targetPath))
{
File.Delete(targetPath);
}
bitmap.Save(targetPath, ImageFormat.Jpeg);
bitmap.Dispose();
}
Marshal.ReleaseComObject(acroPDDoc);
acroPDDoc = null;
}
catch
{
throw;
}
}
//http://www.myexception.cn/c-sharp/1506415.html
//http://www.aspose.com/docs/display/pdfnet/Generate+Thumbnail+Images+from+PDF+Documents
public static void ConvertPDF2Image(string pdfInputPath, string imageOutputPath,
string imageName, int startPageNum, int endPageNum, ImageFormat imageFormat, double resolution)
{
CAcroPDDoc pdfDoc = null;
CAcroPDPage pdfPage = null;
CAcroRect pdfRect = null;
CAcroPoint pdfPoint = null;
// Create the document (Can only create the AcroExch.PDDoc object using late-binding)
// Note using VisualBasic helper functions, have to add reference to DLL
pdfDoc = (CAcroPDDoc)Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.PDDoc", "");
// validate parameter
if (!pdfDoc.Open(pdfInputPath))
{
throw new FileNotFoundException();
}
if (!Directory.Exists(imageOutputPath))
{
Directory.CreateDirectory(imageOutputPath);
}
if (startPageNum <= 0)
{
startPageNum = 1;
}
if (endPageNum > pdfDoc.GetNumPages() || endPageNum <= 0)
{
endPageNum = pdfDoc.GetNumPages();
}
if (startPageNum > endPageNum)
{
int tempPageNum = startPageNum; startPageNum = endPageNum; endPageNum = startPageNum;
}
if (imageFormat == null)
{
imageFormat = ImageFormat.Jpeg;
}
if (resolution <= 0)
{
resolution = 1;
}
// start to convert each page
for (int i = startPageNum; i <= endPageNum; i++)
{
pdfPage = (CAcroPDPage)pdfDoc.AcquirePage(i - 1);
pdfPoint = (CAcroPoint)pdfPage.GetSize();
pdfRect = (CAcroRect)Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.Rect", "");
int imgWidth = (int)((double)pdfPoint.x * resolution);
int imgHeight = (int)((double)pdfPoint.y * resolution);
pdfRect.Left = 0;
pdfRect.right = (short)imgWidth;
pdfRect.Top = 0;
pdfRect.bottom = (short)imgHeight;
// Render to clipboard, scaled by 100 percent (ie. original size)
// Even though we want a smaller image, better for us to scale in .NET
// than Acrobat as it would greek out small text
pdfPage.CopyToClipboard(pdfRect, 0, 0, (short)(100 * resolution));
IDataObject clipboardData = Clipboard.GetDataObject();
if (clipboardData != null && clipboardData.GetDataPresent(DataFormats.Bitmap))
{
string _dir = Path.Combine(imageOutputPath, imageName);
string _path = _dir + "_" + i.ToString() + ".jpg";
if (File.Exists(_path))
{
File.Delete(_path);
}
Bitmap pdfBitmap = (Bitmap)clipboardData.GetData(DataFormats.Bitmap);
pdfBitmap.Save(_path, imageFormat);
pdfBitmap.Dispose();
}
}
pdfDoc.Close();
Marshal.ReleaseComObject(pdfPage);
Marshal.ReleaseComObject(pdfRect);
Marshal.ReleaseComObject(pdfDoc);
Marshal.ReleaseComObject(pdfPoint);
}