How can I rename a file in ASP.NET? - asp.net

In my project I want to rename the file before it is updating. For example a file in my system like Mycontact.xls. I want to rename it as sasi.xls (it is an excel file). How can I write the code in ASP.NET?
Actually I am using a fileupload control to get the file in and rename the file and upload the renamed file in a folder which is in Solution Explorer.

You can do it with the File.Move method eg:
string oldFileName = "MyOldFile.txt";
string newFileName = "MyNewFile.txt";
File.Move(oldFileName, newFileName);

C# does not provide a file rename function, unfortunately. Anyhow, the idea is to do this:
File.Copy(oldFileName, NewFileName);
File.Delete(oldFileName);
You can also use - File.Move.

Be aware that when that code executes, the owner of the file will turn into the identity you have set on your Application Pool on which the website is running.
That account might not have enough permissions to 'create new' or 'delete' files.
I would advise you to place all read/writable files in a seperate location so you can control the security settings seperately on that part. This will also split off the 'only readable files/executables' (like the aspx and such) from the 'read/writable' files.

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Scripting.FileSystemObject seemed to not correctly DeleteFile in Classic ASP

I create a log file with day extension and I append text into this file. One month later, with the same name file (with same date) I need to delete the old file to restart with a new file. For this, I check the DateCreated property.
Everything is correct, the script see that the file is old, it remove it using FileSystemObject.DeleteFile and create a new file. But the new created file has the SAME DateCreated value as the old file! It seemed that the file system does not update the DateCreated value when it create a new file...
My script is an ASP class. I tried to use the CreateTextFile, the OpenTextFile with the force flag, I also tried to close the FileSystemObject and reopen it between the DeleteFile and the OpenTextFile without success.
How to completely erase the file from the filesystem ? Any idea ? Thanks.
It is called "Tunneling" and is part of the filesystem (see here). The solution is in the linked article, wait at least 15 seconds from delete of old file to creation of the new file.

Get file upload data from post data in ASP.NET

I am looping through the posted values on a form with a view to doing something with them (so don't have access to the controls themselves). This is the process I have to take on this project so that is why I'm doing it this way.
On the form I will have a file upload box but I am not sure how I would upload the file that has been selected from it as I can't just do Control.SaveAs(). When I return the posted value using Request.Form.Item[i] I get the file name I chose but not the full path like I would expect.
Can someone point me in the right direction please?
Thanks.
If you want to manipulate the uploaded files directly, and not through a FileUploader control, you should use the Request.Files collection and not the Request.Form
File Upload controls only pass the file name and the contents. I'm not sure why you would need a folder name, especially since the folder name would be for the client - I can't expect that this would have any value to you since you want to save the file on the server.
As I am unsure of your goals, I would recommend using Server.MapPath("~/Folder") to find a suitable folder to save your uploaded files to

ASP.NET localized files

I've got a web page with a link, and the link is suppose to correspond to a PDF is the given user's language. I'm wondering where I should put these PDF files though. If I put them in App_LocalResources, I can't specify a link to /App_LocalResources/TOS_en-US.pdf can I?
The PDF should definitely not be in the App_LocalResources folder. That folder is only for RESX files.
The PDF files can go anywhere else in your app. For example, a great place to put them would be in a ~/PDF folder. Then your links will have to be dynamically generated (similar to what Greg has shown):
string cultureSpecificFileName = String.Format("TOS_{0}.pdf", CultureInfo.CurrentCulture.Name);
However, there are some other things to consider:
You need a way to ensure that you actually have a PDF for the given language. If someone shows up at your site and has their culture specified as Klingon, it's unlikely that you have such a PDF.
You need to decide exactly what the file format will be. In the example given, the file would have to be named TOS_en-US.pdf. It you want to use the 2-letter ISO culture names, use CurrentCulture.TwoLetterISOLanguageName and then the file name would be TOS_en.pdf.
I would store the filename somewhere with an argument in it (i.e. "TOS_{0}.pdf" ) and then just add the appropriate suffix in code:
string cultureSpecificFileName = string.Format("TOS_{0}.pdf", CultureInfo.CurrentCulture);
Does the PDF have to have the same file name for each of the different languages? If not, put them all into a directory and just store the path in your resources file.

how to check whether a file exists before creating it

I am creating an xml file. I need to check first if the file exists or not. If the file does not exist, create it and add the data cmg from a .cs file.
If the file exists, don't create the file just add the data cmg from a .cs file.
My code looks like this:
string filename="c:\\employee.xml";
XmlTextWriter tw=new XmlTextWriter(filename,null);//null represents
the Encoding Type//
tw.Formatting=Formatting.Indented; //for xml tags to be indented//
tw.WriteStartDocument(); //Indicates the starting of document (Required)//
tw.WriteStartElement("Employees");
tw.WriteStartElement("Employee","Genius");
tw.WriteStartElement("EmpID","1");
tw.WriteAttributeString("Name","krishnan");
tw.WriteElementString("Designation","Software Developer");
tw.WriteElementString("FullName","krishnan Lakshmipuram Narayanan");
tw.WriteEndElement();
tw.WriteEndElement();
tw.WriteEndDocument();
tw.Flush();
tw.Close();
so next time we add data to file we need to check if the file exits and add data to xml file
and as we have made empID as a primary key, if user tries to make duplicate entry we need to avoid
Is this possible to do?
if (!File.Exists(filename))
{
// create your file
}
or
if (File.Exists(filename))
{
File.Delete(filename);
}
// then create your file
File class is in System.IO namespace (add using System.IO; to your file)
You can't append records to an XML file, you have to read the file and then rewrite it.
So, just check if the file exists, and read the records from it. Then write the file including all previous records and the new record.
Have a look at the File.Exists method here
Testing for existance of a file before attempting to create it inherently is subject to a "things change after check" race condition. Who can guarantee you that your application isn't preempted and put to sleep for a moment after you checked, someone else creates/deletes that file, your app gets to run again and does exactly the opposite of what you intended ?
Windows (as well as all UN*X variants) supports file open/create modes that allow to perform that create-if-nonexistant/open-if-existant operation as a single call.
As far as .NET goes, this means for your task (create an XML file) you'd first create a System.IO.FileStream with the appropriate modes, see http://msdn.microsoft.com/en-us/library/system.io.filemode.aspx and then pass that stream to the XmlWriter constructor. That's safer than simply performing an "exists" check and hoping for the best.

Send file using Response.BinaryWrite() and delete it afterwards

As part of a Classic ASP Project the user should be able to download a file - which is dynamicly extracted from a zip archive and sent via Response.BinaryWrite() - by simply calling "document.asp?id=[some id here]".
Extracting and sending is not the problem but I need to delete the extracted file after the download finished. I never did any ASP or VBA before and I guess that's why I stuck here.
I tried deleting the file right after Response.WriteBinary() using FileSystemObject.DeleteFile() but this results in a 404-Error on the client-side.
How can I wait till the download finished and then do additional actions?
Edit: This is how my code looks like:
'Unzip a specified file from an archive and put it's path in *document*
set stream = Server.CreateObject("ADODB.Stream")
stream.Open
stream.Type = 1 ' binary
stream.LoadFromFile(document)
Response.BinaryWrite(stream.Read)
'Here I want to delete the *document*
I suspect that the point you are calling the DeleteFile method the file you are trying delete is currently locked by something else, the question is what?
Try including:-
stream.Close()
after your BinaryWrite. Also make sure you've done a similar thing to the component you've used to extract the file. If the component doesn't offer any obviouse "close" methods they trying assigning Nothing to the variables referencing them.
Is it not possible to stream the file into memory, then binary write the stream to the browser, this way the file is never created on the server and there is no need to delete it.
I found a solution: The extracted files are saved in a special directory and everytime a user runs the document.asp it checks this directory for files older than one hour and deletes them.
I think it's the simplest way to manage, but furthermore I would prefer a solution where the document is deleted after downloading.

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