How to do drag and drop in same and different listbox

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C#

I manage to do drag and drop using two different listbox and it works good but how to do the drag and drop in the same listbox ?

sorry i still new with this.

What I have tried:

private void lisBox2_DragDrop(object sender, System.Windows.Forms.DragEventArgs e)
{
if (e.Data.GetDataPresent(DataFormats.StringFormat))
{
string str = (string)e.Data.GetData(DataFormats.StringFormat);

swapBetweenList(selectedIndex, movingIndex);

//lisBox2.Items.Add(str);
}

}