首先在顯示pdf文件，則需先學習pdf.js的運用，先推薦http://blog.csdn.net/xiangcns/article/details/42089189博客，我這邊的重點是怎樣將pdf.js轉換成圖片流。為啥不直接轉圖片，大概是因為在服務器中不允許存圖片，只能將pdf路徑轉圖片流傳輸。直接上demo代碼：我這邊是引用O2S.ComponentModel.DataAnnotations.dll（下載地址http://pan.baidu.com/s/1nUecQ，密碼hep9）
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using O2S.Components.PDFRender4NET;
namespace WebApplication1
{
public partial class WebForm1 : System.Web.UI.Page
{
public enum Definition
{
One = 1, Two = 2, Three = 3, Four = 4, Five = 5, Six = 6, Seven = 7, Eight = 8, Nine = 9, Ten = 10
}
/// <summary>
/// 將PDF文檔轉換為圖片的方法
/// </summary>
/// <param name="pdfInputPath">PDF文件路徑</param>
/// <param name="imageOutputPath">圖片輸出路徑</param>
/// <param name="imageName">生成圖片的名字</param>
/// <param name="startPageNum">從PDF文檔的第幾頁開始轉換</param>
/// <param name="endPageNum">從PDF文檔的第幾頁開始停止轉換</param>
/// <param name="imageFormat">設置所需圖片格式</param>
/// <param name="definition">設置圖片的清晰度，數字越大越清晰</param>
public static List<byte[]> ConvertPDF2Image(string pdfInputPath, int startPageNum, int endPageNum, ImageFormat imageFormat, Definition definition)
{
PDFFile pdfFile = PDFFile.Open(pdfInputPath);
// validate pageNum
if (startPageNum <= 0)
{
startPageNum = 1;
}
if (endPageNum > pdfFile.PageCount)
{
endPageNum = pdfFile.PageCount;
}
if (startPageNum > endPageNum)
{
int tempPageNum = startPageNum;
startPageNum = endPageNum;
endPageNum = startPageNum;
}
// 創建byte數組存放流數組
List<byte[]> byteList = new List<byte[]>();
//循環整個pdf文件去將pdf轉換成圖片流
for (int i = startPageNum; i <= endPageNum; i++)
{
//pdf生成的Bitmap轉換圖片流
Bitmap pageImage = pdfFile.GetPageImage(i - 1, 56 * (int)definition);
MemoryStream ms = new MemoryStream();
pageImage.Save(ms, imageFormat);
pageImage.Dispose();
byte[] byteImg = ms.ToArray();
byteList.Add(byteImg);
}
pdfFile.Dispose();
return byteList;
}
//以上就是將pdf轉圖片流，並沒有將圖片存在本地，以下只是擴展
//將圖片以二進制流
public byte[] SaveImage(String path)
{
FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read); //將圖片以文件流的形式進行保存
BinaryReader br = new BinaryReader(fs);
byte[] imgBytesIn = br.ReadBytes((int)fs.Length); //將流讀入到字節數組中
return imgBytesIn;
}
//現實二進制流代表的圖片
public void ShowImgByByte(byte[] imgBytesIn)
{
Response.ContentType = "image/jpg";//沒有這個會出現亂碼
Response.BinaryWrite(imgBytesIn);
}
}
}
有了圖片流怎樣顯示到頁面了，這里直接使用<img>html圖片控件，直接上代碼
/// <summary>
/// pdf路徑轉圖片流
/// </summary>
/// <returns></returns>
public string PdfPathToImage(string path)
{
//得到圖片流數組
IList<byte[]> imgBytesIn = PdfToImgHelper.ConvertPDF2Image(path, 1, 100, ImageFormat.Jpeg, PdfToImgHelper.Definition.Three);
//拼json數據
StringBuilder strSb = new StringBuilder();
strSb.Append("[");
Int32 _index = 1;
//遍歷將圖片流轉換成Base64
foreach (byte[] s in imgBytesIn)
{
if (imgBytesIn.Count == _index)
{
strSb.Append("{");
strSb.Append("\"value\":\"" + Convert.ToBase64String(s) + "\"");
strSb.Append("}");
}
else
{
strSb.Append("{");
strSb.Append("\"value\":\"" + Convert.ToBase64String(s) + "\"");
strSb.Append("},");
}
_index++;
}
strSb.Append("]");
String strValue = strSb.ToString();
return JsonConvert.SerializeObject(strValue);
}
//pdf路徑轉圖片公共方法
function PdfPathToImage(path) {
$.ajax({
type: "post",
url: "/Evaluation/PdfPathToImage",
data: { "path": path },
async: true,
dataType:'json',
success: function (data) {
//得到base64jsons數據后轉成對象
var p = eval(data);
//如果對象不為空則循環拼接html圖片控件
if (p) {
var _html = "";
for (var item in p) {
_html += '<img src="data:image/png;base64,' + p[item].value + '" style="width:100%" />';
}
$("#masterslider").append(_html);
}
}
});
}
繼續學習，有哪里需要優化的地方，還請提出，逆水行舟不進則退！