I use a button to select erase mode. After selecting erase mode when the user touches the screen, pt.erase is the touch point .

foreach (var item in Draw_Canvas.Children)
{
Line line1 = (Line)item;
if (IsPointBetween(pterase.X, line1.X1, line1.X2))
if (IsPointBetween(pterase.Y, line1.Y1, line1.Y2))
{
_deletedLines.Add(line1);
numberofdeletedlines++;
}
}
foreach (var item in _deletedLines)
{
Draw_Canvas.Children.Remove(item);
Draw_Canvas_Children_Count.Text = Draw_Canvas.Children.Count.ToString();
}

private static bool IsPointBetween(double point, double start, double end)
{
if (start = start) && (point = end) && (point <= start);
}