C#实现PDF转图片

/// <summary>

/// 将PDF文档转换为图片的方法，你可以像这样调用该方法：ConvertPDF2Image("F:\\A.pdf", "F:\\", "A", 0, 0, null, 0);

/// 因为大多数的参数都有默认值，startPageNum默认值为1，endPageNum默认值为总页数，

/// p_w_picpathFormat默认值为ImageFormat.Jpeg，resolution默认值为1

/// </summary>

/// <param name="pdfInputPath">PDF文件路径</param>

/// <param name="p_w_picpathOutputPath">图片输出路径</param>

/// <param name="p_w_picpathName">图片的名字，不需要带扩展名</param>

/// <param name="startPageNum">从PDF文档的第几页开始转换，默认值为1</param>

/// <param name="endPageNum">从PDF文档的第几页开始停止转换，默认值为PDF总页数</param>

/// <param name="p_w_picpathFormat">设置所需图片格式</param>

/// <param name="resolution">设置图片的分辨率，数字越大越清晰，默认值为1</param>

publicstaticvoid ConvertPDF2Image(string pdfInputPath, string p_w_picpathOutputPath,

string p_w_picpathName, int startPageNum, int endPageNum, ImageFormat p_w_picpathFormat, double resolution)

{

Acrobat.CAcroPDDoc pdfDoc = null;

Acrobat.CAcroPDPage pdfPage = null;

Acrobat.CAcroRect pdfRect = null;

Acrobat.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 = (Acrobat.CAcroPDDoc)Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.PDDoc", "");

// validate parameter

if (!pdfDoc.Open(pdfInputPath)) { thrownew FileNotFoundException(); }

if (!Directory.Exists(p_w_picpathOutputPath)) { Directory.CreateDirectory(p_w_picpathOutputPath); }

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 (p_w_picpathFormat == null) { p_w_picpathFormat = ImageFormat.Jpeg; }

if (resolution <= 0) { resolution = 1; }

// start to convert each page

for (int i = startPageNum; i <= endPageNum; i++)

{

pdfPage = (Acrobat.CAcroPDPage)pdfDoc.AcquirePage(i - 1);

pdfPoint = (Acrobat.CAcroPoint)pdfPage.GetSize();

pdfRect = (Acrobat.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 p_w_picpath, 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.GetDataPresent(DataFormats.Bitmap))

{

Bitmap pdfBitmap = (Bitmap)clipboardData.GetData(DataFormats.Bitmap);

pdfBitmap.Save(Path.Combine(p_w_picpathOutputPath, p_w_picpathName) + ".jpg", p_w_picpathFormat);

pdfBitmap.Dispose();

}

}

pdfDoc.Close();

Marshal.ReleaseComObject(pdfPage);

Marshal.ReleaseComObject(pdfRect);

Marshal.ReleaseComObject(pdfDoc);

Marshal.ReleaseComObject(pdfPoint);

}