Other Software > Developer's Corner
C# Rename file with incrementing number - file (1).ext
(1/1)
Renegade:
I've seen people posting code snippets, so here's one...
I was looking around for a way to increment a file name, and didn't come across anything that really worked all that well except for 1 that kind of worked. I've bolstered it up a bit & made it more robust.
Problem:
You want to quickly save file.ext, but not overwrite an existing file with that name. Obviously you want to add an increment for the file name: 1, 2, 3, etc. So you end up with something like this in a folder:
file.ext
file (1).ext
file (2).ext
etc.
Snippet:
This is a bit sloppy in a few places, but it's good enough.
NOTE: This comes out of writing some transcoding software, so the signature there is to allow passing in a file name along with a new file name extension, which is a bit sloppy for general purposes. Basically, you can change the file extension by passing in a different "ext" parameter.
If you don't want a new file extension, simply pass in an empty string for "ext".
--- Code: C# ---/// <summary>/// A function to add an incremented number at the end of a file name if a file already exists. /// </summary>/// <param name="file">The file. This should be the complete path.</param>/// <param name="ext">This can be empty.</param>/// <returns>An incremented file name. </returns>private string AppendFileNumberIfExists(string file, string ext){ // This had a VB tidbit that helped to get this started. // http://www.codeproject.com/Questions/212217/increment-filename-if-file-exists-using-csharp // If the file exists, then do stuff. Otherwise, we just return the original file name. if (File.Exists(file)) { string folderPath = Path.GetDirectoryName(file); // The path to the file. No sense in dealing with this unecessarily. string fileName = Path.GetFileNameWithoutExtension(file); // The file name with no extension. string extension = string.Empty; // The file extension. // This lets us pass in an empty string for the file extension if required. i.e. It just makes this function a bit more versatile. if (ext == string.Empty) { extension = Path.GetExtension(file); } else { extension = ext; } // at this point, find out if the fileName ends in a number, then get that number. int fileNumber = 0; // This stores the number as a number for us. // need a regex here - \(([0-9]+)\)$ Regex r = new Regex(@"\(([0-9]+)\)$"); // This matches the pattern we are using, i.e. ~(#).ext Match m = r.Match(fileName); // We pass in the file name with no extension. string addSpace = " "; // We'll add a space when we don't have our pattern in order to pad the pattern. if (m.Success) { addSpace = string.Empty; // We have the pattern, so we don't add a space - it has already been added. string s = m.Groups[1].Captures[0].Value; // This is the single capture that we are looking for. Stored as a string. // set fileNumber to the new number. fileNumber = int.Parse(s); // Convert the number to an int. // remove the numbering from the string as we're constructing it again below. fileName = fileName.Replace("(" + s + ")", ""); } // Start looping. do { fileNumber += 1; // Increment the file number that we have above. file = Path.Combine(folderPath, // Combine it all. String.Format("{0}{3}({1}){2}", // The pattern to combine. fileName, // The file name with no extension. fileNumber, // The file number. extension, // The file extension. addSpace)); // A space if needed to pad the initial ~(#).ext pattern. } while (File.Exists(file)); // As long as the file name exists, keep looping. } return file;}
Just one of those typical jobs that nobody should have to bother doing again.
ghendric:
This version works pretty good too.
--- Code: C# ---private string GetNextFileName(string fileName) { string extension = Path.GetExtension(fileName); string pathName = Path.GetDirectoryName(fileName); string fileNameOnly = Path.Combine(pathName, Path.GetFileNameWithoutExtension(fileName)); int i = 0; // If the file exists, keep trying until it doesn't while (File.Exists(fileName)) { i += 1; fileName = string.Format("{0}({1}){2}", fileNameOnly, i, extension); } return fileName; }
Ath:
This version works pretty good too.
-ghendric (February 02, 2016, 11:50 AM)
--- End quote ---
Not if a path is prepended to the filename... :o
Navigation
[0] Message Index
Go to full version