I am using
BLOBs in MySQL
C# VS 2010
PDF Reader Component ( added from C#) to
display the PDF
I have an application that uses MySQL as backend and C# as front. i have added a PDF Reader component to my form and i wish to show the pdf on that form. the pdf can be accessed using the loadFile method of the component. My PDFs are stored as BLOBs in MySQL which i extract and copy it to the disk. I then link the path to the loadFile Argument to display my pdf..
This all works fine but now i would like to know if there is a way so that i can display the pdf (stored as a blob in MySQL) without copying it to the hard disk first.
Have you tried reading it directly to a binary array and then sending it to the output? Something along these lines should work. Your equivalent data adapter would work in the first line.
// Generate Report
byte[] data = (byte[])dataTable.Rows[0]["BLOB"];
// Present the generated PDF to the user
Response.Clear();
Response.ContentType = "application/pdf";
Response.AddHeader("content-length", data.Length.ToString());
Response.BinaryWrite(data);
Response.Flush();
Response.Close();
Related
I'm trying to send a zip file to navigator in ASP NET Visual Basic, I do the following:
Response.Clear()
Response.AppendHeader("Content-Disposition", "attachment; filename=" + fileName)
Response.ContentType = "application/zip"
Response.WriteFile(fullPath)
Response.End()
I get this strange characters
How can I send the zip to navigator?
A zip file is NOT a text file. Don't treat it like a text file. Don't try viewing it like a text file.
Rather, a ZIP file is a binary file format. It is a container (also often called an archive) that contains compressed files. What you see there in your screenshot is just the binary data of the ZIP file. Binary data which whatever viewer you used tried to interpret as character codes -- which of course will not yield any sensible result, because a ZIP file is not a text file. It's not.
If you want to get your hands on the files compressed within the ZIP file, you need to uncompress ("unpack") the ZIP file.
By the way, i can see that the compressed file within the ZIP file is presumably a PDF file. Which is also not a text file, but requires a PDF reader/viewer to display/render it (after it has been unpacked from the ZIP file, obviously...).
I got a requirement to create pdf on the fly from the data stored in database.
I am using html, jquery and WCF in my application.
I don't find a way to generate pdf (Show in a browser or as an attachment) using client technology (jquery, or any other client plugins). I tried to use pdf.js, but could not able to succeed. Later I used .net generic handler to generate pdf. I was passing bytearray to handler, in turn pdf started rendering on client.
I got some random issue, then I wrote a sample application to make sure handler is working fine. I used same code with a static text to generate pdf, but it started throwing a error on the client.
Below is the code snippet I used
context.Response.Clear();
context.Response.ContentType = "application/pdf";
context.Response.AddHeader("content-disposition", "inline; filename=download");
context.Response.Write("Hello World");
//context.Response.BinaryWrite(System.Text.Encoding.Default.GetBytes("Hello world"));
//context.Response.BinaryWrite(System.Text.Encoding.UTF8.GetBytes("Hello world"));
context.Response.Flush();
context.Response.End();
I am getting errors on all the browsers
Failed to load pdf document on Chrome.
An error occurred while loading the PDF. PDF.js v0.8.505 (build: da1c944) Message: InvalidPDFException - In mozilla firefox
File does not begin with '%PDF-' in IE.
Note: I tried with aspx page too. I cant create physical file due security issues. If there is any better way of achieving it please let me know. Thanks in advance.
PDF is a standard file format.You cannot write a normal text file and rename it to filename.pdf and wish it to work.
You will need .Net libraries for that.There are lot try googling .Net pdf library
Some Info.
pdf.js is just for viewing in browser.
setting context.Response.ContentType just tells the browser the file its gonna receive,So it can use existing mapped application to open it.Like Adobe browser plugin for pdf file.
I have got stuck in a problem while downloading documents from database.
Currently I'm working in ASP.net project and this is my first career project.
We have some documents which we store in database. The documents(.pdf,.doc,.png,.docx,xls,xlsx) are stored in binary format with their type specified.
I can download one document using Response.write. But now i have to concatenate some documents and then allow user to download on button click.
I have googled a lot. Developers have said that this is impossible. But still i feel that this can be done.
However if this is impossible i thought that i will save these individual documents first at some server location and then zip them and then allow user to download. But how would i be able to save the individual document in their original format at server location.
Please help me out. I'm in big problem.
It is not impossible to read more than one document from a database and zip them up before presenting the zip file to the response stream. You can do this all in process, there is no need to save the documents to the server.
This code uses Ionic.Zip to zip up several files and write them to a MemoryStream:
foreach (var file in files)
{
zipFile.AddEntry(file.FileName, file.ContentBytes); // these are the file bytes
}
var zipMs = new MemoryStream();
zipFile.Save(zipMs);
zipMs.Seek(0, SeekOrigin.Begin);
zipMs.Flush();
The file.FileName includes the extensions (.docx) of the documents and when downloading through the browser, everything is displayed and saved correctly.
When I upload a docx, xlsx or pptx to amazon S3 using aws .net sdk the file is getting uploaded fine and I am able to view the file directly from S3 without any issues. But when I download the file in ASP.net using C# I am getting a warning message (see below) when opening the file:
"Excel found unreadable content in test.xlsx. Do you want to recover the contents of this workbook?" If I click yes, I am able to see all the contents in the document.
similarly I am getting a warning message for .docx file as well.
This is the C# code I am using:
Response.Clear();
Response.ContentType = "application/octet-stream";
Response.AddHeader("content-disposition", "attachment; filename=" + fileName);
Response.OutputStream.Write(Content, 0, Content.Length);
Response.Flush();
HttpContext.Current.ApplicationInstance.CompleteRequest();
Update: When I download the file in windows forms app it is working fine and the problem is with web app only.
What am I doing wrong?
Please help...
More information is needed to figure this out. The code snippet you provided looks OK. The problem looks to be elsewhere in your code... For example, what are you loading inside "Content"?
Also, it would help if you tried uploading and downloading a simple text file, to see what kind of data gets appended.
If Content is a byte[] created from a MemoryStream, make sure you're calling .ToArray() and not .GetBuffer() to get it. If you use .GetBuffer(), you'll potentially get extra bytes on the end, which the office file format probably doesn't like. Your other file types you've tried it with might be more tolerant of extra data they weren't expecting on the end.
I am saving a .doc file to a SQL Server database as varbinary(max) using the C# code below.
I am able to save the file, but when I retrieve the file back and want to display the contents on the web page, my code is downloading the file and I am in great confusion about how to handle it.
The exact functionality I am looking for is the way naukri.com uploads the resume and gives a preview of it. My code is :
byte[] fileContent = new byte[fuResume.PostedFile.ContentLength];
fuResume.PostedFile.InputStream.Read(fileContent, 0, fuResume.PostedFile.ContentLength);
//lblAppliedMessage.Text = ByteArrayToString(fileContent);
//lblAppliedMessage.Text = BitConverter.ToString(fileContent).Replace("-", string.Empty);
byte[] btYourDoc;
btYourDoc = fileContent;
Response.ContentType = "application/ms-word";
Response.AddHeader("Content-Disposition", "inline;filename=yourfilename.doc");
Response.OutputStream.Write(btYourDoc, 0, fileContent.Length);
Response.BinaryWrite(btYourDoc);
Response.End();
The reason your file is getting downloaded instead of displayed is because you're setting the content type to application/ms-word. This tells a browser to download the file (they can't natively handle files of that type so they delegate to an external app).
You'll need to have code that knows how to interpret the MS Word format and convert that to something viewable in a browser (HTML, some kind of plugin that will do that for you, etc). Saving the raw Word document and then sending it back to the client in the same state is basically just having them download a Word file.
squillman is right. There are tons of third party components that do Word -> HTML conversion.
One other option, which may be more appropriate for an intranet site, is to install Word on the server.
An example of this is here:
http://www.c-sharpcorner.com/UploadFile/munnamax/WordToHtml03252007065157AM/WordToHtml.aspx
Effectively, the doc is opened, saved out as HTML, then subsequent requests can retrieve the HTML version of the file for preview.
Office automation server side has many pitfalls, however - see http://support.microsoft.com/kb/257757 for more information.
Here's a good one where the end result it's up to the user whether to download or view the file here's the link but #Squillman is right by putting the Response headers you're telling it to download.