how to find the length of curve in vba?

[Anonymous]

Hi , I am try to create a function that compute the length of a line such as the picture shows on top.

The code I have now only getting the straight line distance. It's there a way to compute the curve distance?

[Hallex]

Try this solution, load lisp code to your acaddoc.lsp,

then try attached .bas file, see for more how to add

lisp routine to your acaddoc.lsp

[Anonymous]

thanks for reply, I will try see if it work.

[Anonymous]

Hello,

Sub LengthCurves()
Dim oEntity As AcadEntity
Dim P1 As Variant
Dim strMessage As String

On Error GoTo Err_LengthCurves

    ThisDrawing.Utility.GetEntity oEntity, P1, vbCrLf & "Select a line, an arc, a circle or a polyline (2D or 3D)"
    
    Select Case oEntity.ObjectName
        Case "AcDbCircle"
            strMessage = "Circle : " & oEntity.Circumference
            
        Case "AcDbArc"
            strMessage = "Arc : " & oEntity.ArcLength
            
        Case "AcDbLine"
            strMessage = "Line : " & oEntity.Length
        
        Case "AcDbPolyline"
            strMessage = "Polyline : " & oEntity.Length
            
        Case "AcDb3dPolyline"
            strMessage = "Polyline 3D : " & oEntity.Length
        
        Case Else
            strMessage = "Error ! The selected entity is not a line, an arc, a circle or a polyline."
    End Select
    

Exit_LengthCurves:
    ThisDrawing.Utility.Prompt strMessage
    Set oEntity = Nothing
    Exit Sub
    
Err_LengthCurves:
    If Err.Number <> -2147352567 Then
        strMessage = "Error : " & Err.Description
    End If
    GoTo Exit_LengthCurves
End Sub

[Anonymous]

Hi,

How can I find only curve or arc lenght in polyline that have lines and arcs?

I try to find lenght with polyline.coordinates. but polyline incluce arc, I can not find arc lenght.

For i = 0 To Sinir - 2 Step 2
            
                xyKoor(0) = PCizgi.Coordinates(i)       'X1
                xyKoor(1) = PCizgi.Coordinates(i + 1)   'Y1
                xyKoor(2) = PCizgi.Coordinates(i + 2)   'X2
                xyKoor(3) = PCizgi.Coordinates(i + 3)   'Y2
                If xyKoor(2) - xyKoor(0) = 0 Then       ' açı hesaplanırken xyKoor(2) - xyKoor(0)=0 ise açı 90 derecesir kodlaması
                    PCizgiAci = PI / 2
                Else
                    PCizgiAci = Atn((xyKoor(3) - xyKoor(1)) / (xyKoor(2) - xyKoor(0))) '* 180 / PI
                End If
                oYaziMesafeY = oYaziMesafe * Cos(PCizgiAci)
                oYaziMesafeX = oYaziMesafe * Sin(PCizgiAci)
                xyKoorMid(0) = (xyKoor(0) + xyKoor(2)) / 2 - oYaziMesafeX
                xyKoorMid(1) = (xyKoor(1) + xyKoor(3)) / 2 + oYaziMesafeY
                
                
                PCizgiUzunluk = 100 * ((xyKoor(0) - xyKoor(2)) ^ 2 + (xyKoor(1) - xyKoor(3)) ^ 2) ^ 0.5
                                
                Set oYazi = ThisDrawing.ModelSpace.AddText("" & Round(PCizgiUzunluk, 0), xyKoorMid, oYaziYuksekligi)
                oYazi.Rotation = PCizgiAci '* PI / 180
                oYazi.Layer = "N-makro-Boy-Parca"
            Next i

[Norman_Yuan]

The easiest way to know the length of each segment between 2 vertices in a polyline is to call Explode() method, which would break down the polyline/LWPolyline at its vertices and return a set entities of either AcadLine, or AcadArc. Then you can get the length of each of them. Do not forget to erase them after calling Explode(), when necessary.