上傳的文件內容預覽

Question

在我的asp.net web應用程序中，我想要一個第三方文件內容預覽工具，通過使用該工具，我將顯示上傳的文件（如jpg或tiff或xls或pdf或txt或doc）

protected void btn_upload_Click(object sender, EventArgs e) 
{ 
    try 
    { 
     if (flup_upload.HasFile) 
     { 
      _fname = flup_upload.FileName.Replace(" ", ""); 
      string ext = Path.GetExtension(_fname).ToLower(); 

      if (ext == ".jpg" || ext == ".jpeg" || ext == ".bmp") 
      { 
       ------ 
      } 
      else if (ext == ".xls" || ext == ".xlsx") 
      { 
       ----- 
      } 
      else if (ext == ".pdf") 
      { 
       ----- 
      } 
      else if (ext == ".tif" || ext == ".tiff") 
      { 
       --- 
      } 
      else if (ext == ".txt") 
      { 
       ---- 
      } 
      else if (ext == ".docx" || ext == ".doc") 
      { 
       ----- 
      } 
     } 
    } 
    catch (Exception ex) 
    { 
    } 
} 

ie上傳文件後（如jpg/tiff/xls/pdf/txt/doc）我想在預覽中顯示文件數據。

Answer 1

你也可以使用ajaxcontroltoolkit文件上傳器來做到這一點;

<td> 
    <asp:Label runat="server" ID="myThrobber" Style="display: none; color: black;"> 
     UpLoading.... 
    </asp:Label> 
    <br /> 
    <Ajax:AsyncFileUpload ID="FileUploadGaurdianPic" runat="server" ThrobberID="myThrobber" 
     MaximumNumberOfFiles="1" 
     OnClientUploadComplete="uploadComplete" OnUploadedComplete="FileUploadGaurdianPic_UploadedComplete" Style="margin-left: 0px" /> 
    <asp:Image runat="server" ID="imageGaurdainTemp" /> // temp image to show 
       </td> 

我們有OnUploadedComplete事件，它是javascript文件的函數名。也是服務器端處理的Uploaded_Complete事件;

protected void FileUploadGaurdianPic_UploadedComplete(object sender, AjaxControlToolkit.AsyncFileUploadEventArgs e) 
{ 
    // storing the file path in session, in-order to get this in futrue and isnert it into the database. note that i am only getting the path here; 
    Session["GuardianPic"] = "/Resources/Images/guardian/" + e.FileName; 
    SaveImage(e.FileName, FileUploadGaurdianPic, 2); 
} 
// here i am generating the thumbnail,and i am uploading the orignal image to the temp path, if you don't need this, remove it. I am only saving the thumbnail to the orignal path; 
private void SaveImage(string FileName, AjaxControlToolkit.AsyncFileUpload uploader, int status) 
{ 
    string path = String.Empty; 
    switch (status) 
    { 
     case 1: 
      path = Server.MapPath("~/Resources/Images/Student/"); 
      break; 
     case 2: 
      path = Server.MapPath("~/Resources/Images/guardian/"); 
      break; 
    } 

    string name = String.Empty; 
    string storedPath = String.Empty; 

    int intThumbWidth = 100; 
    int intThumbHeight = 100; 
    // Check whether the file is really a JPEG by opening it 
    System.Drawing.Image.GetThumbnailImageAbort myCallBack = 
        new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback); 

    //Create Thumbnail 
    Bitmap myBitmap = myBitmap = new Bitmap(uploader.PostedFile.InputStream); ; 

    Bitmap map = new Bitmap(uploader.FileContent); 
    // Save Thumbnail and Assign it to ThumbUrl out parameter 
    System.Drawing.Image myThumbnail = myBitmap.GetThumbnailImage(intThumbWidth, 
             intThumbHeight, myCallBack, IntPtr.Zero); 
    try 
    { 
     string tempPath = Server.MapPath("/Resources/Images/temp/"); 
     if (!Directory.Exists(tempPath)) 
     { 
      Directory.CreateDirectory(tempPath); 
     } 
     if (Directory.Exists(path)) 
     { 
      name = Path.GetFileName(FileName); 
      storedPath = path + name; 
      myThumbnail.Save(storedPath); 
      uploader.SaveAs(tempPath + name); 
     } 
     else 
     { 
      Directory.CreateDirectory(path); 
      name = Path.GetFileName(FileName); 
      storedPath = path + name; 
      myThumbnail.Save(storedPath); 
      uploader.SaveAs(tempPath + name); 
     } 
    } 
    catch (Exception ex) 
    { 
     throw ex; 
    } 
} 

最後，將顯示圖像的javascript函數;

function uploadComplete(sender, args) { 
    var imgDisplay = $get("imageGaurdainTemp"); 
    var img = new Image(); 
    img.onload = function() { 
     imgDisplay.style.cssText = "height:100px;width:100px"; 
     imgDisplay.src = img.src; 
    }; 
    img.src = "/Resources/Images/guardian/" + args.get_fileName(); 

} 

我希望這有助於：d