Is there a built in .NET function to get a unique filename if a filename already exists? So if I try and save MyDoc.doc and it already exists, the file will save with name MyDoc(1).doc, the same way a browser download works for example.
If not, what is the most efficient way to achieve this result?
I am using the File.Move function at the moment btw.
EDIT:
Here's another solution I came up with after Steven Sudit's comment:
static void Main(string[] args)
{
CopyFile(new FileInfo(#"D:\table.txt"), new FileInfo(#"D:\blah.txt"));
}
private static void CopyFile(FileInfo source, FileInfo destination)
{
int attempt = 0;
FileInfo originalDestination = destination;
while (destination.Exists || !TryCopyTo(source, destination))
{
attempt++;
destination = new FileInfo(originalDestination.FullName.Remove(
originalDestination.FullName.Length - originalDestination.Extension.Length)
+ " (" + attempt + ")" + originalDestination.Extension);
}
}
private static bool TryCopyTo(FileInfo source, FileInfo destination)
{
try
{
source.CopyTo(destination.FullName);
return true;
}
catch
{
return false;
}
}
check the name against Regex *.\(\d+\), if it doesn't match, add (1), if it matches increment the number in brackets.
I don't know, but it's not hard to build one yourself:
if filename does not exists then
save file as filename
else
n = 1
while filename(n) exists:
n += 1
save file as filename(n)
As the other answers shows, there are multiple ways of doing this, but one thing to be aware of is if other processes than your can create files you have to be careful, since if you check that a filename is available, by the time you save your new file, some other process might already have saved a file using that name and you'll overwrite that file.
Related
Hi I have a code that you can save file and give specific file naming.
the problem is how can I check if file exist in the folder directory.
What I'm trying to do is like this.
FileInfo fileInfo = new FileInfo(oldPath);
if (fileInfo.Exists)
{
if (!Directory.Exists(newPath))
{
Directory.CreateDirectory(newPath);
}
fileInfo.MoveTo(string.Format("{0}{1}{2}", newPath, extBox1t.Text + "_" + textBox2.Text + "_" + textBox3.Text, fileInfo.Extension));
im trying to add MessageBox.Show in the below
if (!Directory.Exists(newPath))
{
MessageBox.Show("File Exist. Please Rename!");
Directory.CreateDirectory(newPath);
But it does not work. Or is there a way to add extension name at the last part of filename it should like this
Example: STACKOVERFLOWDOTCOME_IDNUM_11162022_0
if STACKOVERFLOWDOTCOME_IDNUM_11162022 exist it will rename to STACKOVERFLOWDOTCOME_IDNUM_11162022_0
it will add _0 at the last part.
One way to do it is to write a method that extracts the directory path, name, and extension of the file from a string that represents the full file path. Then we can create another variable to act as the "counter", which we'll use to add the number at the end of the file name (before the extension). We can then create a loop that checks if the file exists, and if it doesn't we'll increment the counter, insert it into the name, and try again.
For example:
public static string GetUniqueFileName(string fileFullName)
{
var path = Path.GetDirectoryName(fileFullName);
var name = Path.GetFileNameWithoutExtension(fileFullName);
var ext = Path.GetExtension(fileFullName);
var counter = 0;
// Keep appending a new number to the end of the file name until it's unique
while(File.Exists(fileFullName))
{
// Since the file name exists, insert an underscore and number
// just before the file extension for the next iteration
fileFullName = Path.Combine(path, $"{name}_{counter++}{ext}");
}
return fileFullName;
}
To test it out, I created a file at c:\temp\temp.txt. After running the program with this file path, it came up with a new file name: c:\temp\temp_0.txt
Just a quick question if you can help me, please.
In C#, I am creating a directory, if it does not exist. In the next command, I am checking if the directory exists, I will copy some files.
The Problem is, to creating a new directory or Deleting it, takes time and slower than next code execution time.
The software gives an error of "The folder does not exist ".
I used Thread.Sleep(5000); to wait 5 seconds before copying the content to the directory.
It seems to be working but I feel like that this is not how it's supposed to be done. Does anyone know better coding?
string logDirectoryPath = Directory.GetCurrentDirectory() + "\\LogFiles";
if (!Directory.Exists(logDirectoryPath))
{
Directory.CreateDirectory(Directory.GetCurrentDirectory() + "\\LogFiles");
Thread.Sleep(5000);
}
if (Directory.Exists(Directory.GetCurrentDirectory() + "\\LogFiles"))
{
var s = logDirectoryPath + "\\Log_" + DateTime.Now.ToString("dd_MM_yyyy") + ".txt";
using (StreamWriter w = File.AppendText(s))
{
w.WriteLine("--");
w.Write("\r\nLog Entry : ");
w.WriteLine($"{DateTime.Now.ToLongTimeString()} {DateTime.Now.ToLongDateString()}");
}
}
//EDIT
JUST thought maybe I should use a loop?
While(!Directory.Exists(logDirectoryPath))
{
Directory.CreateDirectory(Directory.GetCurrentDirectory() + "\\LogFiles");
}
Use DirectoryInfo
DirectoryInfo di = new DirectoryInfo(#{PATHSTRING});
and use di.Exists to check it exists / di.Create() to create folder
and I'd like to recommend to use logDirectoryPath which you defined already.
like this
DirectoryInfo di = new DirectoryInfo(logDirectoryPath);
if ( !di.Exists ) {
di.Create();
}
my requirement is to move files from one directory to another after certain interval. So basic copy works, but during the next subsequent interval I want to move only the new files.
Following is my approach:
I am creating the file list of both source & target directory in target location, the idea is based on the difference of these two files copy only the files that are new from last iteration.
For 1st iteration it will create a blank file in target indicating copy everything. But my file comparison is hitting issues here, based on logic in below code it's creating this excpetion "System.Linq.Enumerable+d__99`1[System.String]"
Here's the code:
static void Main(string[] args)
{
create_source_fileList();
string source_dir = System.Configuration.ConfigurationSettings.AppSettings["SourceDir"];
string target_dir = System.Configuration.ConfigurationSettings.AppSettings["TargetDir"];
string dpath = target_dir + "Diff" + ".txt";
TextWriter df = new StreamWriter(dpath);
DirectoryInfo sourceinfo = new DirectoryInfo(source_dir);
DirectoryInfo targetinfo = new DirectoryInfo(target_dir);
string[] source_f_list = File.ReadAllLines(target_dir + "Source_File_List.txt");
string[] target_f_list = File.ReadAllLines(target_dir + "Target_File_List.txt");
IEnumerable<String> file_list_diff = source_f_list.Except(target_f_list);
df.WriteLine(file_list_diff);
df.Close();
if (!Directory.Exists(targetinfo.FullName))
{
Directory.CreateDirectory(targetinfo.FullName);
}
foreach (FileInfo fi in sourceinfo.GetFiles())
{
fi.CopyTo(Path.Combine(targetinfo.ToString(), fi.Name), true);
}
create_target_fileList();
}
Need help in fixing this issue,also will this approach down the line work in loop where I will iterate only the names in diff file.
Thanks!!
It's not creating an exception; rather, it's writing the result of calling ToString on an IEnumerable<string> instance. You need to replace:
df.WriteLine(file_list_diff);
with
df.WriteLine(string.Join(Environment.NewLine, file_list_diff));
or, prior to .NET 4:
df.WriteLine(string.Join(Environment.NewLine, file_list_diff.ToArray()));
I am trying to create 2 XML files in the same folder.
For some reason it does create the first one, but does not create the second one.
Could it be that the first one is still being created when an attempt to create the second file is made, and therefore the latter fails?
I don't get any errors with the code:
if (File.Exists(FileNameTextBox.Text + ".AA.xml"))
{
MessageBox.Show("Already exists. renaming to *.old" + Environment.NewLine +
"if there is already an *.old file, this will be deleted.");
if (File.Exists(FileNameTextBox.Text + ".AA.xml.old"))
{
File.Delete(FileNameTextBox.Text + ".AA.xml.old");
}
File.Move(FileNameTextBox.Text + ".AA.xml", FileNameTextBox.Text + ".AA.xml.old");
}
if (!File.Exists(FileNameTextBox.Text + ".AA.xml"))
{
XmlTextWriter textWritter = new XmlTextWriter(FileNameTextBox.Text + ".AA.xml", null);
textWritter.WriteStartDocument();
textWritter.WriteStartElement("Data");
textWritter.WriteEndElement();
textWritter.Close();
}
if (File.Exists("BB.xml"))
{
if (File.Exists("BB.xml.old"))
{
File.Delete("BB.xml.old");
}
File.Move("BB.xml", "BB.xml.old");
}
if (!File.Exists("BB.xml"))
{
XmlTextWriter textWritterPC3 = new XmlTextWriter("BB.xml", null);
textWritterPC3.WriteStartDocument();
textWritterPC3.WriteStartElement("Data");
textWritterPC3.WriteEndElement();
textWritterPC3.Close();
}
Whats in FileNameTextBox.Text? Does it specify a directory path?
Your second file is created without saying which directory. So it will be created in the current directory - which is not necessarily the directory specified by FileNameTextBox.Text
You are not specifying an absolute path for your file names, so you are using whatever the current directory happens to be, which is not reliable. Also you may need to call DirectoryInfo.Refresh() or FileInfo.Refresh() to make sure you are seeing the latest directory information (whether the file exists or not).
The comment is only making the last if case execute the first row.. The last if should look like this. I don't know if it's only in your example.
Your example
if (!File.Exists("BB.xml")) // {
XmlTextWriter textWritterPC3 = new XmlTextWriter("BB.xml", null);
should be
if (!File.Exists("BB.xml")) //
{
XmlTextWriter textWritterPC3 = new XmlTextWriter("BB.xml", null);
textWritterPC3.WriteStartDocument();
textWritterPC3.WriteStartElement("Data");
textWritterPC3.WriteEndElement();
textWritterPC3.Close();
}
I am just learning C# (have been fiddling with it for about 2 days now) and I've decided that, for leaning purposes, I will rebuild an old app I made in VB6 for syncing files (generally across a network).
When I wrote the code in VB 6, it worked approximately like this:
Create a Scripting.FileSystemObject
Create directory objects for the source and destination
Create file listing objects for the source and destination
Iterate through the source object, and check to see if it exists in the destination
if not, create it
if so, check to see if the source version is newer/larger, and if so, overwrite the other
So far, this is what I have:
private bool syncFiles(string sourcePath, string destPath) {
DirectoryInfo source = new DirectoryInfo(sourcePath);
DirectoryInfo dest = new DirectoryInfo(destPath);
if (!source.Exists) {
LogLine("Source Folder Not Found!");
return false;
}
if (!dest.Exists) {
LogLine("Destination Folder Not Found!");
return false;
}
FileInfo[] sourceFiles = source.GetFiles();
FileInfo[] destFiles = dest.GetFiles();
foreach (FileInfo file in sourceFiles) {
// check exists on file
}
if (optRecursive.Checked) {
foreach (DirectoryInfo subDir in source.GetDirectories()) {
// create-if-not-exists destination subdirectory
syncFiles(sourcePath + subDir.Name, destPath + subDir.Name);
}
}
return true;
}
I have read examples that seem to advocate using the FileInfo or DirectoryInfo objects to do checks with the "Exists" property, but I am specifically looking for a way to search an existing collection/list of files, and not live checks to the file system for each file, since I will be doing so across the network and constantly going back to a multi-thousand-file directory is slow slow slow.
Thanks in Advance.
The GetFiles() method will only get you files that does exist. It doesn't make up random files that doesn't exist. So all you have to do is to check if it exists in the other list.
Something in the lines of this could work:
var sourceFiles = source.GetFiles();
var destFiles = dest.GetFiles();
foreach (var file in sourceFiles)
{
if(!destFiles.Any(x => x.Name == file.Name))
{
// Do whatever
}
}
Note: You have of course no guarantee that something hasn't changed after you have done the calls to GetFiles(). For example, a file could have been deleted or renamed if you try to copy it later.
Could perhaps be done nicer somehow by using the Except method or something similar. For example something like this:
var sourceFiles = source.GetFiles();
var destFiles = dest.GetFiles();
var sourceFilesMissingInDestination = sourceFiles.Except(destFiles, new FileNameComparer());
foreach (var file in sourceFilesMissingInDestination)
{
// Do whatever
}
Where the FileNameComparer is implemented like so:
public class FileNameComparer : IEqualityComparer<FileInfo>
{
public bool Equals(FileInfo x, FileInfo y)
{
return Equals(x.Name, y.Name);
}
public int GetHashCode(FileInfo obj)
{
return obj.Name.GetHashCode();
}
}
Untested though :p
One little detail, instead of
sourcePath + subDir.Name
I would use
System.IO.Path.Combine(sourcePath, subDir.Name)
Path does reliable, OS independent operations on file- and foldernames.
Also I notice optRecursive.Checked popping out of nowhere. As a matter of good design, make that a parameter:
bool syncFiles(string sourcePath, string destPath, bool checkRecursive)
And since you mention it may be used for large numbers of files, keep an eye out for .NET 4, it has an IEnumerable replacement for GetFiles() that will let you process this in a streaming fashion.