Revit API extended storage extensible Storage

Revit 2012 API provides extended storage extensible storage to attach data to revit files.
The data is appended to the object. For more information, see the projectinfo example attached to the project file. Using System;
Using System. Collections. Generic;
Using System. LINQ;
Using System. text;

UsingWinform=System. Windows. forms;

UsingAutodesk. revit. UI;
UsingAutodesk. revit. dB;
UsingAutodesk. revit. attributes;

UsingAutodesk. revit. DB. Mechanical;
UsingAutodesk. revit. UI. selection;
UsingAutodesk. revit. applicationservices;

UsingAutodesk. revit. DB. structure;
UsingAutodesk. revit. DB. extensiblestorage;

using system. XML;

namespace revitcodes
{< br> [transactionattribute (Autodesk. revit. attributes. transactionmode. manual)]
Public class External Store: iexternalcommand
{< br> Public result execute (externalcommanddata commanddata, ref string messages, elementset elements)
{

Uiapplication app=Commanddata. Application;
Document Doc=App. activeuidocument. Document;

Reference refwall = App. activeuidocument. selection. pickobject (objecttype. element, " Select a wall " );
Wall = Doc. getelement (refwall) As Wall;
XYZ = App. activeuidocument. selection. pickpoint ( " Select a vertex " );
Storedatainwall (wall, XYZ );

ReturnResult. succeeded;
}

Public VoidStoredatainwall (wall, XYZ datatostore)
{

Transaction createschemaandstoredata= NewTransaction (wall. Document,"Tcreateandstore");

Createschemaandstoredata. Start ();

Schemabuilder=

NewSchemabuilder (NewGUID ("720080cb-da99-40dc-9415-e53f280aa1f0"));

//Allow anyone to read the object

Schemabuilder. setreadaccesslevel (accesslevel. Public );

// restrict writing to this vendor only

schemabuilder. setwriteaccesslevel (accesslevel. vendor);

// required because of restricted write-access

schemabuilder. setvendorid ( " adsk " );

//Create a field to store an XYZ

Fieldbuilder=

Schemabuilder. addsimplefield ("Wiresplicelocation",Typeof(XYZ ));

Fieldbuilder. setunittype (unittype. ut_length );

Fieldbuilder. setdocumentation ("A stored Location Value representing a wiring splice in a wall.");

Schemabuilder. setschemaname ("Wiresplicelocation");

Schema=Schemabuilder. Finish ();//Register the schema object

//Create an entity (object) for this schema (class)

Entity entity= NewEntity (schema );

// get the field from the schema

Field fieldsplicelocation = schema. getfield ( " wiresplicelocation " );

entity. set XYZ > (fieldsplicelocation, datatostore, displayunittype. dut_meters); /// set the value for this entity

wall. setentity (entity); /// store the entity in the element

//Get the data back from the wall

Entity retrievedentity=Wall. getentity (schema );

XYZ retrieveddata=

Retrievedentity. Get<XYZ>(Schema. getfield ("Wiresplicelocation"), Displayunittype. dut_meters );

Createschemaandstoredata. Commit ();

}

}

}

From: http://revit.5d6d.com/thread-1289-1-1.html