关于使用动态语言运行时 (. net)

AutoCAD Managed .NET API允许您使用使用. NET 4.0 引入的动态语言运行时 (DLR)。

使用DLR可以直接访问对象, 而无需:

打开一个对象进行读取或写入, 然后在完成后关闭该对象。
利用事务提交所做的更改。

在使用DLR时获得对象的ObjectId后, 可以直接访问对象的属性和方法。获得ObjectId后, 可以将ObjectId分配给数据类型的变量:

Object in VB.NET
dynamic in C#

获取ObjectId因对象保存到数据库的方式而异。对于存储在表或字典中的对象, 可以通过以下方式访问其ObjectId:

使用ObjectId的 item 方法访问集合中的元素。
创建对表或字典的ObjectId的引用并将其分配给变量, 然后访问数组的元素。

下面的示例代码显示了用于访问存储在与DLR的表或字典中的对象的两个选项:

C#

// Item method

dynamic acCurDb = HostApplicationServices.WorkingDatabase;

dynamic acMSpace = acCurDb.BlockTableId.Item(BlockTableRecord.ModelSpace);

// Reference an element directly from a collection

dynamic acCurDb = HostApplicationServices.WorkingDatabase;

dynamic acBlkTbl = acCurDb.BlockTableId;

dynamic acMSpace = acBlkTbl[BlockTableRecord.ModelSpace];

重要提示: 在使用DLR和C#时, 您需要引用Microsoft.CSharp库。

使用GetEnumerator方法

在将 GetEnumerator 方法与DLR一起使用时, 需要在使用完枚举器对象后显式释放该对象。下面的示例演示如何在完成枚举器时对其进行处置。

C#

dynamic acCurDb = HostApplicationServices.WorkingDatabase;

var acLtypeTbl = acCurDb.LinetypeTableId;

var acTblEnum = acLtypeTbl.GetEnumerator();

...

acTblEnum.Dispose();

使用LINQ查询

您可以利用LINQ查询在使用DLR的图形中查询表或字典的内容。下面的示例演示如何使用 LINQ查询来查询哪些图层在当前图形中具有分配给它们的某些状态。

C#

[CommandMethod("LINQ")]

public static void LINQExample()

{

    dynamic db = HostApplicationServices.WorkingDatabase;

    dynamic doc = Application.DocumentManager.MdiActiveDocument;

    var layers = db.LayerTableId;

    for (int i = ; i < ; i++)

    {

        var newrec = layers.Add(new LayerTableRecord());

        newrec.Name = "Layer" + i.ToString();

        if (i == )

            newrec.IsFrozen = true;

        if (i == )

            newrec.IsOff = true;

    }

    var OffLayers = from l in (IEnumerable<dynamic>)layers

                    where l.IsOff

                    select l;

    doc.Editor.WriteMessage("\nLayers Turned Off:");

    foreach (dynamic rec in OffLayers)

        doc.Editor.WriteMessage("\n - " + rec.Name);

    var frozenOrOffNames = from l in (IEnumerable<dynamic>)layers

                            where l.IsFrozen == true || l.IsOff == true

                            select l;

    doc.Editor.WriteMessage("\nLayers Frozen or Turned Off:");

    foreach (dynamic rec in frozenOrOffNames)

        doc.Editor.WriteMessage("\n - " + rec.Name);

}

示例代码

此页上的示例代码使用以下名称空间:

Autodesk.AutoCAD.Runtime

Autodesk.AutoCAD.ApplicationServices

Autodesk.AutoCAD.DatabaseServices

Autodesk.AutoCAD.Colors

Autodesk.AutoCAD.Geometry

下面的示例代码演示使用和不适用DLR如何将直线添加到当前空间。

[CommandMethod("ADDLINE")]

public static void AddLine()

{

    // Get the current database

    Database acCurDb = HostApplicationServices.WorkingDatabase;

    // 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 a line that starts at 5,5 and ends at 12,3

        using (Line acLine = new Line(new Point3d(, , ),

                                      new Point3d(, , )))

        {

            // Add the new object to the block table record and the transaction

            acBlkTblRec.AppendEntity(acLine);

            acTrans.AddNewlyCreatedDBObject(acLine, true);

        }

        // Save the new object to the database

        acTrans.Commit();

    }

}

C# with Dynamic Language Runtime (DLR)

[CommandMethod("ADDLINE")]

public static void AddLine()

{

    // Get the current database

    dynamic acCurDb = HostApplicationServices.WorkingDatabase;

    // Create a dynamic reference to model or paper space

    dynamic acSpace = acCurDb.CurrentSpaceId;

    // Create a line that starts at 5,5 and ends at 12,3

    dynamic acLine = new Line(new Point3d(, , ),

                              new Point3d(, , ));

    // Add the new object to the current space

    acSpace.AppendEntity(acLine);

}

下面的示例代码演示使用和不使用DLR如何将层添加到当前数据库中。

[CommandMethod("ADDLAYER")]

public static void AddLayer()

{

    // Get the current database

    Database acCurDb = HostApplicationServices.WorkingDatabase;

    using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())

    {

        // Returns the layer table for the current database

        LayerTable acLyrTbl;

        acLyrTbl = acTrans.GetObject(acCurDb.LayerTableId,

                                     OpenMode.ForRead) as LayerTable;

        // Check to see if MyLayer exists in the Layer table

        if (acLyrTbl.Has("MyLayer") != true)

        {

            // Open the Layer Table for write

            acTrans.GetObject(acCurDb.LayerTableId, OpenMode.ForWrite);

            // Create a new layer named "MyLayer"

            using (LayerTableRecord acLyrTblRec = new LayerTableRecord())

            {

                acLyrTblRec.Name = "MyLayer";

                // Assign the ACI color 3 to the new layer

                Color acClr = Color.FromColorIndex(ColorMethod.ByAci, );

                acLyrTblRec.Color = acClr;

                // Add the new layer table record to the layer table and the transaction

                acLyrTbl.Add(acLyrTblRec);

                acTrans.AddNewlyCreatedDBObject(acLyrTblRec, true);

            }

            // Commit the changes

            acTrans.Commit();

        }

        // Dispose of the transaction

    }

}

C# with Dynamic Language Runtime (DLR)

[CommandMethod("ADDLAYER")]

public static void AddLayer()

{

    // Get the current database

    dynamic acCurDb = HostApplicationServices.WorkingDatabase;

    dynamic acLyrTbl = acCurDb.LayerTableId;

    // Check to see if MyLayer exists in the Layer table

    if (acLyrTbl.Has("MyLayer") != true)

    {

        // Create a new layer named "MyLayer"

        dynamic acLyrTblRec = new LayerTableRecord();

        acLyrTblRec.Name = "MyLayer";

        // Assign the ACI color 3 to the new layer

        dynamic acClr = Color.FromColorIndex(ColorMethod.ByAci, );

        acLyrTblRec.Color = acClr;

        // Add the new layer table record to the layer table

        acLyrTbl.Add(acLyrTblRec);

    }

}

下面演示了使用和不使用DLR如何逐步通过并列出当前空间中的所有对象。

[CommandMethod("LISTOBJECTS")]

public static void ListObjects()

{

    // Get the current document and database

    Document acDoc = Application.DocumentManager.MdiActiveDocument;

    Database acCurDb = HostApplicationServices.WorkingDatabase;

    using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())

    {

        // Open the Block table record Model space for write

        BlockTableRecord acSpace;

        acSpace = acTrans.GetObject(acCurDb.CurrentSpaceId,

                                    OpenMode.ForRead) as BlockTableRecord;

        // Step through the current space

        foreach (ObjectId objId in acSpace)

        {

            // Display the class and current layer of the object

            Entity acEnt = (Entity)acTrans.GetObject(objId, OpenMode.ForRead);

            acDoc.Editor.WriteMessage("\nObject Class: " + acEnt.GetRXClass().Name +

                                      "\nCurrent Layer: " + acEnt.Layer +

                                       "\n");

        }

        acTrans.Commit();

    }

}

C# with Dynamic Language Runtime (DLR)

[CommandMethod("LISTOBJECTS")]

public static void ListObjects()

{

    // Get the current document and database

    dynamic acDoc = Application.DocumentManager.MdiActiveDocument;

    dynamic acCurDb = HostApplicationServices.WorkingDatabase;

    // Create a dynamic reference to model or paper space

    dynamic acSpace = acCurDb.CurrentSpaceId;

    // Step through the current space

    foreach (dynamic acEnt in acSpace)

    {

        // Display the class and current layer of the object

        acDoc.Editor.WriteMessage("\nObject Class: " + acEnt.GetRXClass().Name +

                                  "\nCurrent Layer: " + acEnt.Layer +

                                  "\n");

    }

}

巴特西

关于使用动态语言运行时 (. net)

使用GetEnumerator方法

使用LINQ查询

示例代码

C# with Dynamic Language Runtime (DLR)

C# with Dynamic Language Runtime (DLR)

C# with Dynamic Language Runtime (DLR)

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