Form1.vb

 Public Class frmDragDrop

    Private Sub textBoxMouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles tbDragFrom.MouseDown
        tbDragFrom.DoDragDrop(tbDragFrom.Text, DragDropEffects.Move)
    End Sub

    Private Sub textBoxDragEnter(ByVal sender As Object, ByVal e As DragEventArgs) Handles tbDragTo.DragEnter
        If (e.Data.GetDataPresent(DataFormats.Text)) Then
            e.Effect = DragDropEffects.Move
        End If
    End Sub

    Private Sub textBoxDragDrop(ByVal sender As Object, ByVal e As DragEventArgs) Handles tbDragTo.DragDrop
        tbDragTo.Text &= e.Data.GetData(DataFormats.Text).ToString
        tbDragFrom.Text = ""
    End Sub

End Class

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