c# NavisWorks ModelItem isReadOnly() 始终为真

问题描述

我尝试在选定的 NavisWorks ModelItem 的现有类别中添加一些新属性

网络上的例子并不多，它基于相同的 COM 方法。 但是有特殊的方法可以在 API 中添加属性。 只发出对象被锁定的问题。 有什么办法可以解锁吗？

    using ANA = Autodesk.Navisworks.Api;
...
    private void addProperty(string category,string prop,string value)
    {
        var odoc = Autodesk.Navisworks.Api.Application.ActiveDocument;
        ModelItemCollection selectionModelItems = new ModelItemCollection();
        ANA.Application.ActiveDocument.CurrentSelection.SelectedItems.copyTo(selectionModelItems);
        //Clear the current selection
        ANA.Application.ActiveDocument.CurrentSelection.Clear();
        try
        {
            foreach (ModelItem m in selectionModelItems)
            {
                foreach (PropertyCategory p in m.PropertyCategories)
                {
                    if (p.displayName != category) continue;
                    var property = new DataProperty(prop,prop,new VariantData(value));
                    p.Properties.Add(property);
                }
            }
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

执行结果：

解决方法

Navisworks 创建的属性和类别是只读的。 您不能添加或修改由 Navisworks 创建的属性或类别。

您只能创建或添加用户定义的属性 - 使用 COM。 见：

• https://adndevblog.typepad.com/aec/2012/05/create-attributes-and-properties-for-model-objects-using-net-api.html
• https://adndevblog.typepad.com/aec/2012/08/addmodifyremove-custom-attribute-using-com-api.html
• https://forums.autodesk.com/t5/navisworks-api/navisworks-api-add-user-data-tab/td-p/2916866

这是一段代码片段（从上面提到的 xiaodong.liang 论坛帖子中复制），展示了如何使用 COM 添加用户定义的属性：

private void addProperty() {

  ComApi.InwOpState10 state;

  state = ComApiBridge.ComApiBridge.State;

  ModelItemCollection modelItemCollectionIn = new ModelItemCollection(Autodesk.Navisworks.Api.Application.ActiveDocument.CurrentSelection.SelectedItems);

  ComApi.InwOpSelection comSelectionOut =

    ComApiBridge.ComApiBridge.ToInwOpSelection(modelItemCollectionIn);

  ComApi.InwSelectionPathsColl oPaths = comSelectionOut.Paths();

  ComApi.InwOaPath3 oPath = (ComApi.InwOaPath3) oPaths.Last();

  ComApi.InwGUIPropertyNode2 propn = (ComApi.InwGUIPropertyNode2) state.GetGUIPropertyNode(oPath,true);

  ComApi.InwOaPropertyVec newPvec = (ComApi.InwOaPropertyVec) state.ObjectFactory(Autodesk.Navisworks.Api.Interop.ComApi.nwEObjectType.eObjectType_nwOaPropertyVec,null,null);

  ComApi.InwOaProperty newP = (ComApi.InwOaProperty) state.ObjectFactory(Autodesk.Navisworks.Api.Interop.ComApi.nwEObjectType.eObjectType_nwOaProperty,null);

  newP.name = "LXD_Property_Name";

  newP.UserName = "LXD_Property_UserName";

  newP.value = "LXD_Property_Value";

  newPvec.Properties().Add(newP);

  propn.SetUserDefined(0,"LXD_PropertyTab_Name","LXD_PropertyTab_InteralName",newPvec);

}