无法通过某些字符串关键字过滤Directory.Getfiles

Question

I'm trying to list out a file with .TXT extension and also only show file containing "EUROPE_" into a listbox

private void btnDisplay_Click(object sender, EventArgs e)
{            
    listBox1.Items.Clear();
    var files = Directory.EnumerateFiles("C:\\temp\\FOLDER", "*.*", 
        SearchOption.AllDirectories)
        .Where(s =>  s.Contains("*EUROPE*") || s.EndsWith(".TXT"));
}

Nothing displayed when I click the button

Answer 1

You'll need to some adjustments in your code but it's not a bad start.
First of all you can just use the built in wildcard to only get txt-files. Then you can use the Where to determine which file contains "europe". After that you'll need to add each file to the listbox. Otherwise you obviously won't see them.

private void btnDisplay_Click(object sender, EventArgs e)
{
    listBox1.Items.Clear();
    var files = Directory.EnumerateFiles("C:\\temp\\FOLDER", "*.txt", SearchOption.AllDirectories)
    .Where(s => s.ToUpper().Contains("EUROPE"));

    foreach(string file in files){
        listBox1.Items.Add(file);
    }
}

Edit:
You can indeed use the wildcard also to check if it contains europe. In my opinion it's also cleaner and more readable so use this (you'll still need the rest of the code other than this line of course). See this answer which shows this exact method just without the code around it.

Answer 2

You don't have to use the where clause. The following line of code should work:

var files = Directory.EnumerateFiles("C:\\temp\\FOLDER", "*EUROPE_*.txt", SearchOption.AllDirectories)