⤷ Set other file mode

Use FileMode variable for setting some of the valid modes for file.
0 - ReadOnly
1 - WriteOnly
2 - ReadWrite are valid modes.

procedure TForm1.Button2Click(Sender: TObject);
var
  MyFile: TextFile;
begin
  AssignFile(MyFile,Edit1.Text);
  Reset(MyFile);
  FileMode:=ComboBox1.ItemIndex;
  CloseFile(MyFile);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
    Edit1.Text:=OpenDialog1.FileName;
end;
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