Delete files through a button.

Question

Hello I need some help with deleting files .txt through a button with windows forms. Because when I try to do this, I'm getting this error when trying to delete.

Error is:  file is being used in a process..... etc. So I can't delete the file.

Code is very simple: File.Delete(textBox1.Text);

Watched an tutorial and followed it, but it wont let me delete the files.

 

And I have this code too: 

 

if(dlg.ShowDialog() == DialogResult.OK) {

StreamReader reader = new StreamReader(dlg.FileName, Encoding.Default);

textBox1.Text = dlg.FileName;

}

 

if this will help.  

 

 

Could anyone help me?