You can try the StartCap and EndCap feature of the predefined Pen-Object:
'Suppose you have to draw the arrow from Point Pnt1 to Point Pnt2:
Dim Graph As Graphics = Me.CreateGraphics()
Dim Pen1 As New Pen(Color.Blue, 5)
Pen1.StartCap = Drawing2D.LineCap.ArrowAnchor
Pen1.EndCap = Drawing2D.LineCap.DiamondAnchor
Graph.DrawLine(Pen1, Pnt1.X, Pnt1.Y, Pnt2.X, Pnt2.Y)
This code draws a nice arrow onto your form:
Drawing a simple arrow in Visual Basic
objEnum As IDictionaryEnumerator - the data from which the graph has to be drawn.
intItemCount As Integer - number of items to show in a graph (you can get from the DictionaryEnumerator itself).
strGraphTitle As String - title has to be drawn for the graph.
Xaxis As Integer - starting X axis.
Yaxis As Integer - starting Y axis.
MaxWidth As Int16 - maximum width of the graph (for calculation purpose).
MaxHt As Int16 - maximum height of the graph (for calculation purpose).
clearForm As Boolean - whether the Form has to clear or not.
Optional ByVal SpaceRequired As Boolean - whether space is required in between 2 graphs.
The graph has to be called in the Paint event of the Form and the parameters should be resized in the Resize event of the Form.
LoadColorArray procedure is used to have required colors to draw the graph. Because, if we use RGB, overall the graph will not be good visibly.
The parameter clearForm can be used when you need to show 2 graphs in the same Form; it will be useful then...
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Public Sub drawBarChart(ByVal objEnum As IDictionaryEnumerator, _
ByVal intItemCount As Integer, ByVal strGraphTitle As String, _
ByVal Xaxis As Integer, ByVal Yaxis As Integer, _
ByVal MaxWidth As Int16, ByVal MaxHt As Int16, _
ByVal clearForm As Boolean, _
Optional ByVal SpaceRequired As Boolean = False)
Dim intGraphXaxis As Integer = Xaxis
Dim intGraphYaxis As Integer = Yaxis
Dim intWidthMax As Integer = MaxWidth
Dim intHeightMax As Integer = MaxHt
Dim intSpaceHeight As Integer
Dim intMaxValue As Integer = 0
Dim intCounter As Integer
Dim intBarWidthMax
Dim intBarHeight
Dim strText As String
Try
Dim grfx As Graphics = CreateGraphics()
If clearForm = True Then
grfx.Clear(BackColor)
End If
grfx.DrawString(strGraphTitle, New Font("VERDANA", 12.0, _
FontStyle.Bold, GraphicsUnit.Point), _
Brushes.DeepPink, intGraphXaxis + (intWidthMax / 4), _
(intGraphYaxis - intHeightMax) - 40)
intBarHeight = CInt(intHeightMax / intItemCount)
intSpaceHeight = _
CInt((intHeightMax / (intItemCount - 1)) - intBarHeight)
If Not objEnum Is Nothing Then
While objEnum.MoveNext = True
If objEnum.Value > intMaxValue Then
intMaxValue = objEnum.Value
End If
End While
End If
intBarWidthMax = CInt(intWidthMax / intMaxValue)
If Not objEnum Is Nothing Then
intCounter = 1
objEnum.Reset()
grfx.DrawLine(Pens.Black, intGraphXaxis, _
intGraphYaxis, intGraphXaxis + intWidthMax, _
intGraphYaxis)
grfx.DrawLine(Pens.Black, intGraphXaxis, _
intGraphYaxis, intGraphXaxis, _
(intGraphYaxis - intHeightMax) - 25)
While objEnum.MoveNext = True
intGraphYaxis = intGraphYaxis - intBarHeight
grfx.DrawRectangle(Pens.Black, _
New Rectangle(intGraphXaxis, intGraphYaxis, _
intBarWidthMax * objEnum.Value, intBarHeight))
grfx.FillRectangle(objColorArray(intCounter), _
New Rectangle(intGraphXaxis, intGraphYaxis, _
intBarWidthMax * objEnum.Value, intBarHeight))
strText = "(" & objEnum.Key & "," & objEnum.Value & ")"
grfx.DrawString(strText, New Font("VERDANA", 8.0, _
FontStyle.Regular, GraphicsUnit.Point), _
Brushes.Black, intGraphXaxis + _
(intBarWidthMax * objEnum.Value), intGraphYaxis)
intCounter += 1
If SpaceRequired = True Then
intGraphYaxis = intGraphYaxis - intSpaceHeight
End If
If intCounter > objColorArray.GetUpperBound(0) Then
intCounter = 1
End If
End While
If clearForm = True Then
grfx.Dispose()
End If
End If
Catch ex As Exception
Throw ex
End Try
End Sub