Make line clickable VB.NET

Hi there, i am drawing some lines on a System.Drawing.Graphics object.

for example
gMyGraphics.DrawLine(pMyPen, 0 + lineStartMargin, lineYpos, lineWidth + lineStartMargin, lineYpos)

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I want that line to be clickable and run a function when its clicked.
Any ideas?
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You have two options

1) Keep the points at which the line exists and when mouse is clicked within the container of the line, get the coordinates and if the coordinates match with any of those of the line then execute the function you want.

2) Use a control such as label instead of drawing a line. This will obviously work only if you want to draw a straight horizontal line.
Mohamed AbowardaSenior Software EngineerCommented:
You can use panel or picture box and set the BackgroundImage property to a line you have drawn in image file then handle the panel or picture box Click event.

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Mike TomlinsonHigh School Computer Science, Computer Applications, Digital Design, and Mathematics TeacherCommented:
You can calculate the distance between the mouse click and the line and consider it a hit if it is less than a certain threshold.  I recommend somewhere around 5 to 7 pixels.

So the mouse click coords would be (Px, Py) and the endpoints of the line would be (Ax, Ay) and (Bx, By):
Private Function PointToLineDist( _
            ByVal Px As Single, ByVal Py As Single, _
            ByVal Ax As Single, ByVal Ay As Single, _
            ByVal Bx As Single, ByVal By As Single) As Single

        Dim q As Single

        If (Ax = Bx) And (Ay = By) Then
            ' A and B passed in define a point, not a line.
            ' Point to Point Distance
            Return PointToPointDist(Px, Py, Ax, Ay)
            ' Distance is the length of the line needed to connect the point to
            ' the(segment)such that the two lines would be perpendicular.

            ' q is the parameterized value needed to get to the intersection
            q = ((Px - Ax) * (Bx - Ax) + (Py - Ay) * (By - Ay)) / _
                ((Bx - Ax) * (Bx - Ax) + (By - Ay) * (By - Ay))

            ' Limit q to 0 <= q <= 1
            ' If q is outside this range then the Point is somewhere past the 
            ' endpoints of our segment.  By setting q = 0 or q = 1 we are 
            ' measuring the actual distacne from the point to one of the 
            ' endpoints(instead)
            If q < 0 Then q = 0
            If q > 1 Then q = 1

            ' Distance
            Return PointToPointDist( _
                Px, Py, (1 - q) * Ax + q * Bx, (1 - q) * Ay + q * By)
        End If
    End Function

    Private Function PointToPointDist(ByVal Ax As Single, ByVal Ay As Single, _
                                   ByVal Bx As Single, ByVal By As Single) As Single
        ' PointToPointDist = SquareRoot((Bx - Ax)^2 + (By - Ay)^2)
        Return Math.Sqrt((Bx - Ax) * (Bx - Ax) + (By - Ay) * (By - Ay))
    End Function

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