revit api扩展存储extensible storage

    public Result Execute(ExternalCommandData commandData,ref string message,ElementSet elements){UIDocument uiDoc = commandData.Application.ActiveUIDocument;Document doc = uiDoc.Document;// Create transaction for working with schemaTransaction trans = new Transaction(doc, "Extensible Storage");trans.Start();// Select a wall elementWall wall = null;try{Reference r = uiDoc.Selection.PickObject(ObjectType.Element,new WallSelectionFilter());wall = doc.GetElement(r) as Wall;}catch (Autodesk.Revit.Exceptions.OperationCanceledException){message = "Nothing selected; please select a wall to attach extensible data to.";return Result.Failed;}Debug.Assert(null != wall, "expected a wall to be selected");if (null == wall){message = "Please select a wall to attach extensible data to.";return Result.Failed;}// Create a schema builderSchemaBuilder builder = new SchemaBuilder(_guid);// Set read and write access levelsbuilder.SetReadAccessLevel(AccessLevel.Public);builder.SetWriteAccessLevel(AccessLevel.Public);// Note: if this was set as vendor or application access, // we would have been additionally required to use SetVendorId// Set name to this schema builderbuilder.SetSchemaName("WallSocketLocation");builder.SetDocumentation("Data store for socket related info in a wall");// Create field1FieldBuilder fieldBuilder1 =builder.AddSimpleField("SocketLocation", typeof(XYZ));// Set unit typefieldBuilder1.SetUnitType(UnitType.UT_Length);// Add documentation (optional)// Create field2FieldBuilder fieldBuilder2 =builder.AddSimpleField("SocketNumber", typeof(string));//fieldBuilder2.SetUnitType(UnitType.UT_Custom);// Register the schema objectSchema schema = builder.Finish();// Create an entity (object) for this schema (class)Entity ent = new Entity(schema);Field socketLocation = schema.GetField("SocketLocation");ent.Set<XYZ>(socketLocation, new XYZ(2, 0, 0), DisplayUnitType.DUT_METERS);Field socketNumber = schema.GetField("SocketNumber");ent.Set<string>(socketNumber, "200");wall.SetEntity(ent);// Now create another entity (object) for this schema (class)Entity ent2 = new Entity(schema);Field socketNumber1 = schema.GetField("SocketNumber");ent2.Set<String>(socketNumber1, "400");wall.SetEntity(ent2);// Note: this will replace the previous entity on the wall // List all schemas in the documentstring s = string.Empty;IList<Schema> schemas = Schema.ListSchemas();foreach (Schema sch in schemas){s += "\r\nSchema Name: " + sch.SchemaName;}TaskDialog.Show("Schema details", s);// List all Fields for our schemas = string.Empty;Schema ourSchema = Schema.Lookup(_guid);IList<Field> fields = ourSchema.ListFields();foreach (Field fld in fields){s += "\r\nField Name: " + fld.FieldName;}TaskDialog.Show("Field details", s);// Extract the value for the field we createdEntity wallSchemaEnt = wall.GetEntity(Schema.Lookup(_guid));XYZ wallSocketPos = wallSchemaEnt.Get<XYZ>(Schema.Lookup(_guid).GetField("SocketLocation"),DisplayUnitType.DUT_METERS);s = "SocketLocation: " + Format.PointString(wallSocketPos);string wallSocketNumber = wallSchemaEnt.Get<String>(Schema.Lookup(_guid).GetField("SocketNumber"));s += "\r\nSocketNumber: " + wallSocketNumber;TaskDialog.Show("Field values", s);trans.Commit();return Result.Succeeded;}