Q. What is Enterprise Metadata Management?

Introduction to Enterprise Metadata Management

Enterprise metadata management (EMM) is a set of features introduced in Microsoft SharePoint Server 2010 that enable taxonomists, librarians, and administrators to create and manage terms and sets of terms across the enterprise.

The managed metadata service: is a service application that enables the use of managed metadata and

allows you to share content types across site collections and across Web applications. The service publishes a term store and content types, and the metadata is consumed via the managed metadata connection. A managed metadata service and connection are created when the metadata service application is created.

Managed Metadata Service Application Creating the service application requires the administrator to specify the database to be used as the term store. When you create new managed terms, or when users add managed keywords, these terms are stored in the database. Like other service applications, the managed metadata service can be published to provide access to other Web applications.
When a service application is published, a URL to the service is created.
 The administrator of another Web application can create a connection to your service by using this URL.
In addition to sharing metadata, you can also use the managed metadata service to share content types. By creating a new managed metadata service and specifying a site collection as the content type hub, you can share all content types in the site collection’s content type gallery.

You can create multiple managed metadata service applications. This provides the capability to share multiple term stores and content types from multiple site collections. Each service must specify a different term store during the creation process, and a new database will be created if it does not exist.

Managed Metadata Service ConnectionThe connection provides access to the service. When you create a managed metadata service, a connection to the service is automatically created in the same Web application as the service. Web applications can have connections to multiple services. Several properties are specified as part of the connection. Values for each of these properties must be specified as part of configuring the service connection.

Default keyword location Specifies that the term store will be used to store new managed keywords. This provides the capability for sharing and managing a common set of keywords across site collections.

Default term set location Specifies where to store term sets when new site columns are created. This provides the capability for sharing and managing a common set of terms across site collections.

Use content types Makes content types associated with this managed metadata service available to users of sites in this Web application.Push-down content type publishing updates from the content type gallery to subsites and lists by using the content type whether to update existing instances of the changed content types in subsites and libraries.

Creating and Deploying Custom aspx Page as Feature and Solution Package

There are two ways to deploy a custom aspx page in SharePoint.

1. Using VseWss extensions project. Here you won't need to create a solution package manually. All the files need to create a solution package are created by the VS extensions itself. See the related Post Deploy Custom Css file in 12 hive. You can use same method to deploy your Custom aspx page.

2. The second way is creating a solution package around your asp.net webapplication so that the pages in the webapplictaion can be deployed in sharepoint. This requires you to manually create all the solution related files (I mean manifest.xml, feature.xml, elements.xml and .ddf file).


In this Post, we will create a solution package manually for a asp.net webapplication project, so that the custom aspx page created in asp.net web application can be deployed in SharePoint's Layouts folder.

Below are the Steps that you can follow :

1. Create a New WebApplication Project.

2. Create a new folder "MyCustomFolder" in the solution explorer and Add your custom aspx page (along with cs file) under it.

3. Add two more xml files in the same folder with names as elements.xml and feature.xml.

The Elements.xml File should look like below -

<elements xmlns="<a href=">http://schemas.microsoft.com/sharepoint/">
<module name="Pages" url="_layouts">
<file url="CustomPage.aspx" name="CustomPage.aspx" type="GhostableInLibrary"> </file>
</module>
</elements>
</div>

Note : Add Module name as “Pages” and url as ” _Layouts “


The Feature.xml File should look like below -

<feature id="79DD53E7-8719-45b0-8E25-C2450B3E3F14" title="Project.CustomPage" description="Custom Page" scope="Web" version="1.0.0.0" hidden="false" xmlns="http://schemas.microsoft/sharepoint/">
<elementmanifests>
<elementmanifest location="elements.xml">
<elementfile location="CustomPage.aspx"> </elementfile> </elementmanifest>
</elementmanifests>
</feature></div>


4. Now, Create another xml file in the Project and name it as manifest.xml

The manifest.xml should look like below -

<solution xmlns="<a href=">http://schemas.microsoft.com/sharepoint/" SolutionId="A5A9C1C2-4EBF-40db-935F-66085A9E0BE8">
<rootfiles>
<rootfile location="TEMPLATE\LAYOUTS\MyCustomFolder\CustomPage.aspx">
</rootfile>
<assemblies>
<assembly deploymenttarget="GlobalAssemblyCache" location="Project.CustomPage.dll">
<safecontrols>
<safecontrol assembly="Project.CustomPage Version=1.0.0.0, Culture=neutral, PublicKeyToken=a28586c97e90b41f" namespace=" Project.CustomPage" typename="*" safe="True"> </safecontrol>
</safecontrols>
</assembly>
</assemblies>
</rootfiles>
</solution>

Note : If you are using some code behind with your aspx page, then change the Inherit tag in the aspx page to inherit from the assembly of the project.

For e.g. change the tag to

Inherits="NameSpace.Class, NameSpace, Version=1.0.0.0, Culture=neutral, PublicKeyToken=2ef8d0c4bab8980b" Debug="true"

You dont need to deploy .cs file with the Project. The code is accessed via its .dll .

5. Finally Create the .ddf file ( its simply a text file with name as .ddf)

.ddf file would be something like below -

.OPTION Explicit ; Generate errors.Set CompressionType=MSZIP

.Set UniqueFiles=Off.Set

DiskDirectory1=Package

.Set CabinetNameTemplate=Project.CustomPage.wsp

manifest.xml

bin\ Project.CustomPage.dll

.Set DestinationDir=TEMPLATE\LAYOUTS\CustomPage.aspx

;sets the feature directory.

Set DestinationDir=CustomPageFolder

;adds the feature to the feature directory

MyCustomFolder\feature.xml

;adds the element to the feature

MyCustomFolder\elements.xml

I have created an empty folder in the Project with a name as “Package” to save the .wsp file in it.


6. Sign the project with a key (Project Properties -> "signing tab" and browse your .snk key) and Build the Project.

7. Now, Add and deploy the .wsp solution which is under Package Folder in SharePoint using stsadm commands.

What is the main difference between using SPListItem.Update() and SPListItem.SystemUpdate()?

Ans. Using SystemUpdate() will not create a new version and will also retain timestamps.

Impersonation in Sharepoint (RunWithElevatedPrivileges)

Although not recommended, there may be times when you need your code to perform certain functions that the current user does not have the necessary permissions to perform.

The SPSecurity class provides a method (RunWithElevatedPrivileges) that allows you to run a subset of code in the context of an account with higher privileges than the current user.
The premise is that you wrap the RunWithElevatedPrivileges method around your code. And also In certain circumstances, such as when working with Web forms, you may also need to set the AllowSafeUpdates method to true to temporarily turn off security validation within your code. If you use this technique, it is imperative that you set the AllowSafeUpdates method back to false to avoid any potential security risks.

Code example

{
SPSite mySite = SPContext.Current.Site;
SPWeb myWeb = mySite.OpenWeb();

//Using RunWithElevatedPrivileges

SPSecurity.RunWithElevatedPrivileges(delegate()
{
// Get references to the site collection and site for the current context.
// The using statement makes sures these references are disposed properly.

using (SPSite siteCollection = new SPSite(mySite.ID))
{

using (SPWeb web = siteCollection.OpenWeb(myWeb.ID))
{

web.AllowUnsafeUpdates = true;

try
{
//Your code
}

web.AllowUnsafeUpdates = false;

//siteCollection = null;
//web = null;

}

What is a Field Control?

Ans. Field controls are server controls that provide the basic field functionality of SharePoint. For example a Inputbox (single line text) to enter the title of the item. You can create your own FieldControl by inheriting classes from BaseFieldControl namespace.

Difference between Application Pages, Site Pages and Content Pages?

Application Pages - An application page is deployed once per Web server and cannot be customized on a site-by-site basis. They stay in 12 hive folder structure, mostly under layouts folder.

Site Pages - These are pages that make up the site interface and are specific to one site or site collection.They mostly get stored in the content database of the site collection.

Content Pages - Site Page which contains webpart or other custom components. This Page is stored in database. They mostly get stored in the content database of the site collection.

What are event receivers or event Handlers in SharePoint?

Ans. Event Receivers or Event handlers are created to handle the basic actions or events against an item,list\library, a web or a site. There are two kinds of events in sharepoint.

Synchronous Events: Like Itemadding (not added yet), Uploading (document not uploaded yet) etc.

Asynchronous Events: ItemAdded (after item is added), Uploaded(after a document is uploaded)

Events receivers can be written to override an event for e.g. ItemAdded event to change the name of an Item once it is added.

You will normally, find it under C:\Program Files\Common Files\ shared\web server extensions\12\bin.