c# - C# windows form doubled file name in listbox

Question

i made like this:

 private void button4_Click(object sender, EventArgs e)
        {
            {
                DirectoryInfo dinfo = new DirectoryInfo(@"C:\Users\Administrator\source\repos\Generator\Generator\bin\Debug\net5.0-windows");
                FileInfo[] Files = dinfo.GetFiles("*.txt");
                foreach (FileInfo file in Files)
                {
                   listBox1.Items.Add(file.Name);
                }


            }
        }

When i will click button4, show me all .txt from folder in listBox1. But when i add next one .txt in folder and click again, names are double. How to make that 1 file name = 1 position ?

Sorry for my english.

标签： c#windowsformsbuttonlistbox

Answer 1

You should clear the listbox before re-adding the filenames.

private void button4_Click(object sender, EventArgs e)
{
    DirectoryInfo dinfo = new DirectoryInfo(@"C:\Users\Administrator\source\repos\Generator\Generator\bin\Debug\net5.0-windows");
    FileInfo[] Files = dinfo.GetFiles("*.txt");

    // Clear all previous items from the listbox
    listBox1.Items.Clear();

    foreach (FileInfo file in Files)
    {
       listBox1.Items.Add(file.Name);
    }
}