How to check file exist on server in asp.net

Quick access. Search related threads. Remove From My Forums. Answered by:. Archived Forums. Web Forms Data Controls. Sign in to vote. User posted Greetings again, Per Wei's assistance with this issue Thanks again Wei , two field names, filename, server are database fields. Let's assume that the value of filename is M. Any ideas how to handle?

Thank you again in advance for your help. Thursday, May 30, AM. User posted Create a CSS class that sets the background colors you want. Monday, June 3, PM. User posted Hello simflex, To check if file exists on server Try with this , I hope this will help you if File. Exists Server. User posted So, how do I use this when my function has two parameters? MapPath virtualPath ; return System. MapPath virtualPath and ran my code, every Listen link is getting disabled.

I only want to disable the links that have no audio file on the server. Can this be tweaked? Thanks a lot for your assistance. Thursday, May 30, PM. User posted Get the physical path from a relative reference. MapPath string. User posted Thanks mgebhard, What do you mean by a separate application? Which of the above will not work, both solutions you provided? Remove From My Forums. Answered by:. Archived Forums. Web Forms. Sign in to vote. User posted i have a file on server and want to check whether that file or not from another server.

Saturday, January 21, PM. User posted Does the web server have access to the file? Tuesday, January 24, PM. User posted have you tried "Impersonation"? User posted can you telll me how to use impersontion? User posted kk.. Sunday, January 22, AM. User posted i m getting error : Access to the path denied: i want 1.

User posted Code for impersonation: using System. Principal; using System. I'm using ASP. I think this question actually is - "How can I know the file uploaded by a user from a web form already exists on the server. Add a comment.

Active Oldest Votes. IO namespace: bool System. Example: using System; using System. WriteLine "Resume file does not exist. What do you mean by "selected path"? There is Server. See here: stackoverflow. NET it's easiest to always work with full file path strings. There is a static. NET class at System. Path you can use to tear apart a FilePath string if needed for extension, directory, and filename components, etc.

I recommend you 'accept his answer'. As to your follow on question above-- 'how to get a selected file path' If that's what you meant you need to be more specific -- there are so many different paradigms.

StackOverflow has a myriad of very technical users and we're all peers Also make sure we know what you're seeking so we can provide it to you. JimLahman actually, it's the other way round: normal C strings are escaped, which means that e. Show 1 more comment.

To test whether a file exists in. NET, you can use System. Exists String. James Ogden James Ogden 5 5 silver badges 11 11 bronze badges. Exists Server. Moreover, for a hosted site as opposed to on your own computer you typically don't even know what the correct path is when you're writing the code. But sometimes like now, for writing a file you do need a complete path. The solution is to use the MapPath method of the Server object. This returns the complete path to your website.

You can then concatenate additional information onto whatever the method returns in order to create a complete path.

In this example, you add a file name. You can read more about how to work with file and folder paths in Introduction to ASP. This folder is a special folder in ASP. The WriteAllText method of the File object writes the data to the file.

This method takes two parameters: the name with path of the file to write to, and the actual data to write. Notice that the name of the first parameter has an character as a prefix.

This tells ASP. For more information, see Introduction to ASP. On your development computer this is not typically an issue. However, when you publish your site to a hosting provider's web server, you might need to explicitly set those permissions.

If you run this code on a hosting provider's server and get errors, check with the hosting provider to find out how to set those permissions. In the previous example, you used WriteAllText to create a text file that's got just one piece of data in it. If you call the method again and pass it the same file name, the existing file is completely overwritten. However, after you've created a file you often want to add new data to the end of the file. You can do that using the AppendAllText method of the File object.

In the website, make a copy of the UserData. This code has one change in it from the previous example. The methods are similar, except that AppendAllText adds the data to the end of the file. Even if you don't need to write data to a text file, you'll probably sometimes need to read data from one. To do this, you can again use the File object. You can use the File object to read each line individually separated by line breaks or to read individual item no matter how they're separated.

This procedure shows you how to read and display the data that you created in the previous example. The code starts by reading the file that you created in the previous example into a variable named userData , using this method call:. The code to do this is inside an if statement. When you want to read a file, it's a good idea to use the File.

Exists method to determine first whether the file is available. The code also checks whether the file is empty. The body of the page contains two foreach loops, one nested inside the other.

The outer foreach loop gets one line at a time from the data file. In this case, the lines are defined by line breaks in the file — that is, each data item is on its own line.