Drag and Drop File on Windows Forms

Dialog to open a file

Create a project of type “Windows Forms Application”:

On form add a textbox and a button like this:

Click twice on button “Open” to generate the click event:

Add the follow code:

using (OpenFileDialog dialog = new OpenFileDialog())
{
   if (dialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
   {
      textBox1.Text = dialog.FileName;
   }
}

Run your application.

Drag file from explorer to your Application

We need to set the property “allowdrop” to true on our textbox:

Now we need to implement the event DragOver on the textbox component:

At event created we need to add the follow code:

private void textBox1_DragOver(object sender, DragEventArgs e)
{
   if (e.Data.GetDataPresent(DataFormats.FileDrop))
      e.Effect = DragDropEffects.Link;
   else
      e.Effect = DragDropEffects.None;
}

The method “.Data.GetDataPresent(DataFormats.FileDrop)” check if is a File droping. In case true, we set the effect to “Link”.

Now we need to create event DragDrop on textbox:

At event created put this:

private void textBox1_DragDrop(object sender, DragEventArgs e)
{
   string[] files = e.Data.GetData(DataFormats.FileDrop) as string[]; // get all files droppeds
   if (files != null && files.Any())
      textBox1.Text = files.First(); //select the first one
}

Run your application from generated “.exe”, from debug doesn’t work.