c# exclude file extentions from a foreach statement

Question

I have a foreach statement that is part this function:

try
{
  string pathToFiles = sourceTB.Text;
  DirectoryInfo dirInfo = new DirectoryInfo(pathToFiles);
  int i = 0; 

  foreach (var files in dirInfo.EnumerateFiles())
  {
    //Do stuff here
  }
  MessageBox.Show("Process Successful", "Completed");
}
catch
{
  MessageBox.Show("Process failed", "Failed");
}

I would like to be able to code it so that it will read the entire contents of the selected folder (this is working fine), but I am trying to make it so it will skip any files with a certain file extension.

For Example if every file in the folder was a .txt file and I wanted to leave out the .jpg files.

I have tried a few ways to achieve this such as:

var allFilesFromFolder = Directory.GetFiles(pathToFiles);
var filesToExclude = Directory.GetFiles(pathToFiles, "*.jpg");
var filetoInclude = allFilesFromFolder.Except(filesToExclude);

and this:

var files = Directory.GetFiles(pathToFiles).Where(name => !name.EndsWith(".jpg"));

but both of these bring errors into to the code and wont fit in the foreach loop when cycles through the files.

Is there any way to achieve this?

What exactly is going wrong? You code (at least the second variant) seems ok. — Sergey.quixoticaxis.Ivanov, Jul 14 '17 at 15:47
Possible duplicate of [Directory.GetFiles of certain extension](https://stackoverflow.com/questions/13301053/directory-getfiles-of-certain-extension) — Vladimir Arustamian, Jul 14 '17 at 15:48
Works fine for me. I don't see where you are getting an error. — Bob G, Jul 14 '17 at 15:49
The way you're trying to do it should be fine, however another approach is to keep your original code `foreach (var files in dirInfo.EnumerateFiles())` and then put and `if` inside the loop to check the file extension and skip it with `continue` it if it is jpg. — Racil Hilan, Jul 14 '17 at 15:50

Steve · Accepted Answer · 2017-07-14T17:02:24.413

3

You can prepare a list of extensions you don't want to process and then use that list while enumerating the FileInfo class returned by a DirectoryInfo.EnumerateFiles

List<string> excluded = new List<string>() {".jpg", ".png"};
foreach (var file in dirInfo.EnumerateFiles().Where(x => !excluded.Contains(x.Extension))
{
   //Do stuff here
}

edited Jul 14 '17 at 17:02

answered Jul 14 '17 at 15:50

Steve

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Works perfect. Thankyou! – Jul 14 '17 at 15:58
1

Just a side note about variable naming, it should be singular `var file`. I know the OP has it plural, but that's either a typo or reflects incorrect understanding of the `foreach` loop, so it would be better if fixes in the accepted answer. – Racil Hilan Jul 14 '17 at 16:05
thanks for the note @RacilHilan I am trying to improve the cleanliness of my code for others to read so I appreciate your post. – Jul 14 '17 at 16:12
1

A final note. You can add a ToLower() to the Extension property to be sure to match also files with an upper case extension – Steve Jul 14 '17 at 17:03

score 0 · Answer 2 · answered Jul 14 '17 at 16:01

The way you're trying to do it should work fine, but you can also include a pattern in your original code, for instance this will give you all text files:

foreach (var file in dirInfo.EnumerateFiles("*.txt"))
{
  //Do stuff here
}

Another approach is to keep your original code and then put and check the extension inside:

foreach (var file in dirInfo.EnumerateFiles("*.txt"))
{
  if(file.Extension == ".jpg")
    continue;

  //Do stuff here
}

c# exclude file extentions from a foreach statement

2 Answers2