弧長寸法を記入する(.NET)

弧長寸法は、円弧の長さを計測し、円弧記号が上または前に付いた寸法値を表示します。始点と終点の間の単なる距離ではなく、円弧の実際の長さの寸法が必要なときは、弧長寸法を使用します。

ArcDimension オブジェクトのインスタンスを作成することで、弧長半径寸法を記入します。ArcDimension オブジェクトのインスタンスを作成するときは、寸法を定義する一連のパラメータが必要です。新しい ArcDimension オブジェクトを作成するときは、次のパラメータを指定する必要があります。

注: システム変数 DIMARCSYM は、円弧記号を表示するかどうか、および寸法値に対して円弧記号を表示する位置をコントロールします。

弧長寸法を記入する

次の例は、モデル空間に弧長寸法を記入します。

VB.NET

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Geometry
 
<CommandMethod("CreateArcLengthDimension")> _
Public Sub CreateArcLengthDimension()
    '' Get the current database
    Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument
    Dim acCurDb As Database = acDoc.Database

    '' Start a transaction
    Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()

        '' Open the Block table for read
        Dim acBlkTbl As BlockTable
        acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, _
                                     OpenMode.ForRead)

        '' Open the Block table record Model space for write
        Dim acBlkTblRec As BlockTableRecord
        acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), _
                                        OpenMode.ForWrite)

        '' Create an arc length dimension
        Using acArcDim As ArcDimension = New ArcDimension(New Point3d(4.5, 1.5, 0), _
                                                          New Point3d(8, 4.25, 0), _
                                                          New Point3d(0, 2, 0), _
                                                          New Point3d(5, 7, 0), _
                                                          "<>", _
                                                          acCurDb.Dimstyle)

            '' Add the new object to Model space and the transaction
            acBlkTblRec.AppendEntity(acArcDim)
            acTrans.AddNewlyCreatedDBObject(acArcDim, True)
        End Using

        '' Commit the changes and dispose of the transaction
        acTrans.Commit()
    End Using
End Sub

C#

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;
 
[CommandMethod("CreateArcLengthDimension")]
public static void CreateArcLengthDimension()
{
    // Get the current database
    Document acDoc = Application.DocumentManager.MdiActiveDocument;
    Database acCurDb = acDoc.Database;

    // Start a transaction
    using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())
    {
        // Open the Block table for read
        BlockTable acBlkTbl;
        acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,
                                        OpenMode.ForRead) as BlockTable;

        // Open the Block table record Model space for write
        BlockTableRecord acBlkTblRec;
        acBlkTblRec = acTrans.GetObject(acBlkTbl[BlockTableRecord.ModelSpace],
                                        OpenMode.ForWrite) as BlockTableRecord;

        // Create an arc length dimension
        using (ArcDimension acArcDim = new ArcDimension(new Point3d(4.5, 1.5, 0),
                                                        new Point3d(8, 4.25, 0),
                                                        new Point3d(0, 2, 0),
                                                        new Point3d(5, 7, 0),
                                                        "<>",
                                                        acCurDb.Dimstyle))
        {

            // Add the new object to Model space and the transaction
            acBlkTblRec.AppendEntity(acArcDim);
            acTrans.AddNewlyCreatedDBObject(acArcDim, true);
        }

        // Commit the changes and dispose of the transaction
        acTrans.Commit();
    }
}

VBA/ActiveX コード リファレンス

Sub CreateArcLengthDimension()
    Dim dimObj As AcadDimArcLength
    Dim arcCenterPoint(0 To 2) As Double
    Dim firstPoint(0 To 2) As Double
    Dim secondPoint(0 To 2) As Double
    Dim arcPoint(0 To 2) As Double
 
    ' Define the dimension
    arcCenterPoint(0) = 4.5: arcCenterPoint(1) = 1.5: arcCenterPoint(2) = 0
    firstPoint(0) = 8: firstPoint(1) = 4.25: firstPoint(2) = 0
    secondPoint(0) = 0: secondPoint(1) = 2: secondPoint(2) = 0
    arcPoint(0) = 5: arcPoint(1) = 7: arcPoint(2) = 0
 
    ' Create the arc length dimension in Model space
    Set dimObj = ThisDrawing.ModelSpace. _
                     AddDimArc(arcCenterPoint, firstPoint, _
                     secondPoint, arcPoint)
 
    ZoomAll
End Sub

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