用.NET阻止AutoCAD对象被选中

本文主要是介绍用.NET阻止AutoCAD对象被选中，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

原文：Preventing AutoCAD objects from being selected using .NET

在上一篇文章中我们看到如何阻止实体在选择中被高亮显示。这一片文章我们将会看到如何阻止实体被选中。再次感谢 Balaji Ramamoorthyt 提供的代码

我们采用的基本方案和上一篇相似，我们维护一份我们想阻止被选择的对象的DXF名称列表。但是它可以很容易的被改进成用其他的条件来讲对象从选择集中删除

如果我们使用单个实体选择函数（GetEntity()）而不是用GetSelection()，我们可能需要使用另外一种方式来过滤：我们可能需要用PrompEntityOptions.AddAllowedClass()来允许特定的类型。但是我们也可以使用这一技术用于实体选择。尤其是我们用其他的条件(例如不是基于实体类型)来阻止实体被选择

using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
using Autodesk.AutoCAD.Runtime;
using System.Collections.Generic;
using System.Text;namespace PreventSelection
{public class Test : IExtensionApplication{void OnSelectionAdded(object sender, SelectionAddedEventArgs e){ObjectId[] addedIds = e.AddedObjects.GetObjectIds();for (int i=0; i < addedIds.Length; i++){ObjectId oid = addedIds[i];if (IsInList(oid.ObjectClass.DxfName)){e.Remove(i);}}}[CommandMethod("US")]public static void Unselect(){Document doc = Application.DocumentManager.MdiActiveDocument;Editor ed = doc.Editor;// Print the list of currently unhighlighted classesed.WriteMessage(ListToPrint());// Get the type to add to the listPromptResult pr =ed.GetString("\nEnter the type of object to stop from " +"being selected: ");if (pr.Status != PromptStatus.OK)return;if (IsInList(pr.StringResult)){ed.WriteMessage("\nItem already in the list.");}else{AddToList(pr.StringResult);ed.WriteMessage("\nItem added to the list.");}}// Would call this command RS, but it's taken by RSCRIPT,// so using the somewhat unwieldy UUS, instead[CommandMethod("UUS")]public static void Ununselect(){Document doc = Application.DocumentManager.MdiActiveDocument;Editor ed = doc.Editor;// Print the list of currently unhighlighted classesed.WriteMessage(ListToPrint());// Get the type to remove from the listPromptResult pr =ed.GetString("\nEnter the type of object to remove from the " +"list: ");if (pr.Status != PromptStatus.OK)return;if (!IsInList(pr.StringResult)){ed.WriteMessage("\nItem not currently in the list.");}else{RemoveFromList(pr.StringResult);ed.WriteMessage("\nItem removed from the list.");}}void IExtensionApplication.Initialize(){Document doc = Application.DocumentManager.MdiActiveDocument;Editor ed = doc.Editor;ed.SelectionAdded +=new SelectionAddedEventHandler(OnSelectionAdded);}void IExtensionApplication.Terminate(){Document doc = Application.DocumentManager.MdiActiveDocument;Editor ed = doc.Editor;ed.SelectionAdded -=new SelectionAddedEventHandler(OnSelectionAdded);}// The list of types to unhighlightstatic List<string> _unhighlighted = new List<string>();// Add a type to the listpublic static void AddToList(string name){string upper = name.ToUpper();if (!_unhighlighted.Contains(upper)){_unhighlighted.Add(upper);}}// Remove a type from the listpublic static void RemoveFromList(string name){string upper = name.ToUpper();if (_unhighlighted.Contains(upper)){_unhighlighted.Remove(upper);}}// Check whether the list contains a typepublic static bool IsInList(string name){return _unhighlighted.Contains(name.ToUpper());}// Get a string printing the contents of the listpublic static string ListToPrint(){string toPrint;if (_unhighlighted.Count == 0){toPrint ="\nThere are currently no objects in the list " +"to stop from being selected.";}else{StringBuilder sb =new StringBuilder("\nObjects of these types will not be selected:");foreach (string name in _unhighlighted){sb.Append(" " + name);}toPrint = sb.ToString();}return toPrint;}}
}

这篇关于用.NET阻止AutoCAD对象被选中的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！

---