C#.Net: Circle MText Objects Matching String Entered By User

In my last post we created a C#.Net program to place a red circle around all MText entities in a drawing. Let's add some code to allow the user to enter a specific string value to place circles around. The descriptive inline comments that were in the first program are not duplicated here for clarity.

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.EditorInput;

using Autodesk.AutoCAD.Geometry;

namespace SLD_Demo

{

    public class MTextTools

    {

        [CommandMethod("SLDcirText")]

        public void SLDcirText()

        {

            //get current document

            Document acDoc =

                Application.DocumentManager.MdiActiveDocument;

            //get AutoCAD database

            Database acCurDb = acDoc.Database;

            //get string to search for

            String sldStrToSrch = SLDgetStringFromUser(acDoc);

            //start db transaction

            using (Transaction acTrans =

                acCurDb.TransactionManager.StartTransaction())

            {

                //open block table

                BlockTable bt = (BlockTable)acTrans.GetObject

                    (acCurDb.BlockTableId, OpenMode.ForRead);

                BlockTableRecord btr = (BlockTableRecord)

                    acTrans.GetObject(bt[BlockTableRecord.ModelSpace],

                    OpenMode.ForRead);

                //iterate through block table to locate mtext objects

                foreach (ObjectId id in btr)

                {

                    //open each object to read

                    DBObject obj = acTrans.GetObject

                        (id, OpenMode.ForRead);

                    //only deal with MText objects

                    MText dbMText = obj as MText;

                    //if current object is Mtext

                    if (dbMText != null)

                    {

                        //assign value of current MText object to a new

                        //String variable

                        String curTxtValue = dbMText.Contents;

                        //now compare to the string entered by user

                        /*I am using the Equals method and overriding to

                         not be case sensitive. This method is returning

                         a boolean value and we are looking for true.

                         There are several string comparison methods.

                         The Contains method would return true if the

                         string entered by user is a part of any Mtext

                         entities. The code for this is:

                           if (curTxtValue.Contains(sldStrToSrch))

                        */

                        if (string.Equals(sldStrToSrch, curTxtValue,

                            StringComparison.CurrentCultureIgnoreCase))

                        {

                            //draw a circle around the mtext entity

                            SLDdrawCir(acCurDb, acTrans, dbMText);

                        }

                    }

                }

                //commit the transaction so we do not leave the db open

                acTrans.Commit();

            }

        }

        //function to get text string from user

        public String SLDgetStringFromUser(Document acDoc)

        {

            PromptStringOptions pStrOpts = new PromptStringOptions(

                "\nFind What: ");

            //control the prompt string options to behave like we want

            //such as allow spaces to be entered

            pStrOpts.AllowSpaces = true;

            //retrieve the string entered by user

            PromptResult pStrRes = acDoc.Editor.GetString(pStrOpts);

            //and assign to a new string variable

            String sldStr = pStrRes.StringResult;

            //return the string variable to calling function

            return sldStr;

        }

        //function to draw circle around an MText object

        public void SLDdrawCir(Database acCurDb,

            Transaction acTrans, MText MtextObj)

        {

            //define a new point object for the center point of circle

            Point3d cenPoint = new Point3d();

            //use the location method of the Mtext object to define

            //the center point coordinates

            cenPoint = MtextObj.Location;

            //define a new Circle object

            /*we use the center point defined above, assign a diameter

             and assign a color using the ColorIndex method from the

             circle object*/

            Circle textCir = new Circle();

            textCir.Center = cenPoint;

            textCir.Diameter = 1.0;

            textCir.ColorIndex = 1;

            //now add the circle to the drawing (model space)

            /*We need to add it to the block table, this is the same

             basic operations when adding geometry to a drawing*/

            BlockTable acBlkTbl;

            acBlkTbl = acTrans.GetObject(

                acCurDb.BlockTableId, OpenMode.ForRead) as BlockTable;

            BlockTableRecord acBlkTblRec;

            acBlkTblRec = acTrans.GetObject(

                acBlkTbl[BlockTableRecord.ModelSpace],

                OpenMode.ForWrite)

                as BlockTableRecord;

            acBlkTblRec.AppendEntity(textCir);

            acTrans.AddNewlyCreatedDBObject(textCir, true);

        }

    }

}

To test this build the solution and NETLOAD the .dll into AutoCAD. Place some MText objects in the drawing and then type in SLDcirText at the command line. You will be prompted to enter a string to search for. Enter a string and regardless of case the matching strings should be circled.

C#.Net: Circle All MText Objects in a Drawing

This program places a red circle around all MText objects in a drawing. The functionality is pretty much stripped down to a basic starting point. This should be a fun program to add additional features to in order to continue exploring C#.Net concepts.

The inline comments should explain each segment, a few things to point out are:

• We use two functions - one as our entry point with the AutoCAD defined command, and the other as a support function called by the main one.
• We use some of the provided object methods from the AutoCAD API. For example, as we work with an MText object we use the predefined Location method to determine the coordinates.

Some of the features we will add on in future posts can be:

• Prompt options to allow the user to change the circle color, size, etc.
• Place circles around Text objects as well as MText.
• Place circles around Text/MText objects that match a string provided by the user.

Here is the C# code:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.EditorInput;

using Autodesk.AutoCAD.Geometry;

namespace SLD

{

    public class SLDtools

    {

        [CommandMethod("SLDcirText")]

        public void SLDcirText()

        {

            //get current document

            Document acDoc =

                Application.DocumentManager.MdiActiveDocument;

            //get AutoCAD database

            Database acCurDb = acDoc.Database;

            //start db transaction

            using (Transaction acTrans =

                acCurDb.TransactionManager.StartTransaction())

            {

                //open block table

                /*all drawing objects are in the block table so in

                 order to look at each object we need to have the

                 block table open for read*/

                BlockTable bt = (BlockTable)acTrans.GetObject

                    (acCurDb.BlockTableId, OpenMode.ForRead);

                BlockTableRecord btr = (BlockTableRecord)

                    acTrans.GetObject(bt[BlockTableRecord.ModelSpace],

                    OpenMode.ForRead);

                //iterate through block table to locate mtext objects

                /*this foreach loop will loop through the block table

                 record looking at each object in the drawing.*/

                foreach (ObjectId id in btr)

                {

                    //open each object to read

                    DBObject obj = acTrans.GetObject

                        (id, OpenMode.ForRead);

                    //only deal with MText objects

                    MText dbMText = obj as MText;

                    //if current object is Mtext then draw a circle

                    //around it

                    if (dbMText != null)

                    {

                        //call separate function to draw circle

                        /*here we want to pass the acad db, the current

                         transaction, and the mtext object that we want

                         to draw a circle around*/

                        SLDdrawCir(acCurDb, acTrans, dbMText);

                    }

                }

                //commit the transaction so we do not leave the db open

                acTrans.Commit();

            }

        }

        //function to draw circle around an MText object

        public void SLDdrawCir(Database acCurDb,

            Transaction acTrans, MText MtextObj)

        {

            //define a new point object for the center point of circle

            Point3d cenPoint = new Point3d();

            //use the location method of the Mtext object to define

            //the center point coordinates

            cenPoint = MtextObj.Location;

            //define a new Circle object

            /*we use the center point defined above, assign a diameter

             and assign a color using the ColorIndex method from the

             circle object*/

            Circle textCir = new Circle();

            textCir.Center = cenPoint;

            textCir.Diameter = 1.0;

            textCir.ColorIndex = 1;

            //now add the circle to the drawing (model space)

            /*We need to add it to the block table, this is the same

             basic operations when adding geometry to a drawing*/

            BlockTable acBlkTbl;

            acBlkTbl = acTrans.GetObject(

                acCurDb.BlockTableId, OpenMode.ForRead) as BlockTable;

            BlockTableRecord acBlkTblRec;

            acBlkTblRec = acTrans.GetObject(

                acBlkTbl[BlockTableRecord.ModelSpace],

                OpenMode.ForWrite)

                as BlockTableRecord;

            acBlkTblRec.AppendEntity(textCir);

            acTrans.AddNewlyCreatedDBObject(textCir, true);

        }

    }

}

To test this build the solution and NETLOAD the .dll into AutoCAD. Place some MText objects in the drawing and then type in SLDcirText at the command line.

C#.Net : Add Geometry to AutoCAD

I am fresh off a great AU experience and as usual I was very inspired by several different speakers and products. A lot of inspiration came from the AutoCAD programming side and I want to start providing more C#.Net samples on this blog. It fits nicely with the Streamlined concept of managing a CAD environment and it will help me advance my knowledge in the subject.

I have posted a few previous C#.Net posts: getting started, and a layer application. However, if I am going to provide more code samples I decided I need a better method for getting my source code from Visual Studio into a blog post other than manually modifying the HTML. I installed CopySourceAsHtml for this exact purpose and it works great! (very quick to setup). A couple of things to note though:

• I do not believe this add-in works with Visual Studio Express editions.
• The current version of CopySourceAsHtml does not appear to be available for VS2010 but it was very simple to modify the add-in file after installing.
• To use the add-in just select the source code then select Copy As HTML... from the Edit pulldown.
• I pasted my code into Word then just did another select all and pasted that into the blogger editor (for some reason going directly from VS to Blogger I lost the coloring).

So here is my first result of using this add-in, a simple program to add some geometry into AutoCAD (line).

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Geometry;


namespace SLD_Demo
{
    public class SLD_DrawTools
    {
        [CommandMethod("SLDdrawLine")]
        public void SLDdrawLine()
        {
            //initiate drawing objects
            /*In order to work with AutoCAD from .Net we do that through
            the object hierarchy that AutoCAD is built from. The
            Application is the root object. We then dig into that to get
            to the current document. We will create a new Document object
            called acDoc. From there we go one level further to access
            the AutoCAD database for the current document.
            */
            Document acDoc = Application.DocumentManager.MdiActiveDocument;
            Database acCurDb = acDoc.Database;

            //start db transaction
            /*reading and creating entities within AutoCAD requires a
            transaction with the AutoCAD document database (objects
            defined above)*/
            using (Transaction
                acTrans = acCurDb.TransactionManager.StartTransaction())
            {
                //define line
                /*when a new line object is created there are a few
                constructor methods that can be used. In this example we
                will define 2 new 3D point objects and then pass those
                to the new line object as paramaters*/
                Point3d startPoint = new Point3d(0,0,0);
                Point3d endPoint = new Point3d(0,5,0);
                Line sldLine = new Line(startPoint, endPoint);

                //open block table and create new record
                /*Note, at this point our new line is only defined within
                our program, it is not in the AutoCAD drawing yet. In order
                to add the defined line to the drawing we need to create
                a new record in the AutoCAD document database.*/
                BlockTable acBlkTbl;
                acBlkTbl = acTrans.GetObject(
                    acCurDb.BlockTableId, OpenMode.ForRead) as BlockTable;

                BlockTableRecord acBlkTblRec;
                acBlkTblRec = acTrans.GetObject(
                    acBlkTbl[BlockTableRecord.ModelSpace],
                    OpenMode.ForWrite)
                    as BlockTableRecord;

                //add line to drawing
                /*now that we have created a new block table record we
                can add our new line to it.*/
                acBlkTblRec.AppendEntity(sldLine);
                acTrans.AddNewlyCreatedDBObject(sldLine, true);

                //end the transaction with the AutoCAD database
                /*This is a very important step. When we begin a
                transaction with the AutoCAD database it has to be
                terminated (commited). Otherwise future AutoCAD
                commands will not function and the drawing will likely
                crash*/
                acTrans.Commit();
            }
        }
    }
}