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Wednesday, 17 August 2011

Fault Contracts in WCF services

Recently I was asked to raise a custom exception in the WCF Services which will be handled on the client side. As a normal programmer I created a custom exception in my service and left on the client side to handle. Assuming that it will be sent on the client side as it is. Instead it showed me this error.
Fault Contracts in WCF services

Little as I knew, something clicked me that if we pass/return the custom objects it has to be defined as a contract. As contracts are the only thing that WCF uses to communicate with the client.
I googled a bit around and came with the concept of Fault Contracts. Consider I have created a custom exception class as defined below
[DataContract()]
    public class CustomException
    {
        [DataMember()]
        public string Title;
        [DataMember()]
        public string ErrorMessage;
        [DataMember()]
        public int ErrorCode;
        [DataMember()]
        public string StackTrace;       
    }

Now if I throw this exception directly to the client, it would not recognize it. Hence any method which can raise this exception should specify the attribute while defining it. (as shown below)
[ServiceContract()]
    public interface IService
    {
        [OperationContract()]
        [FaultContract(typeof(CustomException))]
        String MyMethod(string inputParams);
    }
The next step is throwing the exception from the method
public String MyMethod (string inputParams)
        {
        CustomException error = new CustomException();
        error.Title = "my custom exception for fault contracts";
        error.ErrorMessage = "Error in MyMethod";
        error.ErrorCode = 1001;
        error.StackTrace = "custom stack trace";
        throw new FaultException(error,"Reason: Testing the Fault contract");
        }

While on the client side , you can catch the thrown exception as shown below,
        try
        {
        Proxy.MyMethod(“Kalashnikov”);
        }
        catch (FaultException<MyService.CustomException> ex)
        {
        //Process the Exception as thrown
        }

Custom Login page for Sharepoint 2010 Mixed mode authentication

In one of my previous post, I discussed about adding form authentication to your SharePoint site. I Hope it was useful ! This post is dedicated to customize the Login Screen for the SharePoint site


Recently I had to configure Windows authentication and forms authentication in SharePoint 2010. It should not have been difficult in 2010 as it have mixed mode authentication. But what lacked were enough tutorials/articles. So I thought to share it!
First of all we need a landing page for our application. It is good to have common landing page for windows authentication and SharePoint authentication. So that every unauthenticated request can be re-directed to single page. By default SharePoint have a dropdown to select the authentication mode and then proceeds based on selection.
Custom Login page for Sharepoint 2010 Mixed mode authentication
We can also have our own login page with the same functionality. I have designed something like this.
Custom Login page for Sharepoint 2010 Mixed mode authentication

You have to specify the login page URL in web.config. By default it is “/_login/default.aspx”
<forms loginUrl="/_layout/MyLoginPage.aspx" />
Note : MyLoginPage.aspx should be application page as user will not have access to SharePoint page,  as he /she is not authenticated yet.
As now as we have our login page ready, we need to add the code for login button and hyperlink to intranet access
1.       Forms Authentication via Login Button
2.       Windows Authentication via hyperlink ‘Click here for intranet access’

1.       Forms Authentication
In the event handler of login click event we can authenticate the user with the following method.
SPClaimsUtility.AuthenticateFormsUser(Context.Request.UrlReferrer,
                   Username,
                          Password);
This method authenticates a form user by checking username and password. When the user is validated this object persists a cookie to the client for later use.

2.       Windows Authentication
LnkIntranet.NavigateUrl = Page.ResolveUrl(@"~/_windows/default.aspx?ReturnUrl=/YouLandingPage.aspx");

SharePoint will authentication the windows logged in user
On Success it will redirect to the ‘ReturnUrl’ page mentioned in the parameter
On Error it will redirect to ‘AccessDenied.aspx’

Tuesday, 14 June 2011

Difference between Sharepoint List and Document Library

Difference between Sharepoint List and Document Library


• In to a document library we can upload document which are not blocked file type and some content, which get stored in Content database. A list on the other hand a just piece of data, just like SQL table although it is possible to store binary content in to list as well as using attachment.
• And with a document library we can SPFileCollection.add(string, stream) – Document Library Accept a stream, means the content can be in memory, or disk or even a TCP/IP socket.
• But with List we Only Can SPAttachmentCollection.Add(string, byte) only accepting a byte , means the attachment must fit entirely in one continuous block memory. It this is something you do with large file , your server memory may become fragmented
• And we Can Publish a InfoPath Form Template in document Library, and this problem is rise when we submit the Form in different place then where you published the form.
• We can’t create Folder in List but we can create in Doc. Library
• Document library the Check in Check out functionality but not in List.
• Document library support the Major and Minor Version of files and Folders. But in List only support the Major version. So that two people cannot change the same content at concurrently.
• Some type of list have different functions like for instance people being only able to read their own posts, but these are not available in every type of list and are not available at all with document libraries and other libraries.
• List have one special List Content type, same as list Library has also Document Library type content type.
• Both list and Library are support Event handler and Workflow like features.

Saturday, 16 April 2011

Change the windows authentication to Form Based authentication for SharePoint 2007 Site




I am assuming  that you have already created a SharePoint site on your machine which is already running with a windows authentication as it is requires minimum configuration to start with. If you don’t have a site running on windows authentication you can create it using the following link
We will split our tutorial in 6 steps as below.
Step 1: Create SQL Server Database for membership
Step 2: Adding user to the database.
Step 3: Web.config Modifications
Step 4: Add newly created user to the SharePoint site
Step 5: Enable the “Forms” Authentication
Step 6: Run the application

Step 1: Create SQL Server Database for membership


To enable Form based authentication, we need to have a database to store the user information such as user credentials, roles associated, etc. To create the database Microsoft has provided a utility which creates a database for us. Utility can be found here %windir%\Microsoft.Net\Framework\vx.x.xxxxx on your server. Refer the image below.
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Run the aspnet_regsql application and it will start the ASP.net SQL Server wizard. Refer the image below
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Click Next >
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Select the first option “Configure SQL Server for application services” and then click next >
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

It will display the server name. Select the proper Authentication and Database (I have kept it at default aspnetdb) Click Next >
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

It will start creating the database “aspnetdb” in your SQL Server and required tables, store procedures for user membership. Click on finish and exit the wizard.
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

You can open SQL Server to check if the database is created and what tables/Store Procedures wizard has created.
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Step 2: Adding user to the database.

We have all the necessary stored procedure to create new user in the database. Using these procedures we can create our custom user interface to add user to the database or we can use the membership seeder tool provided by Codeplex
For simplicity, We will use these tool to create user. Extract the download folder  and execute the MembershipSeeder.exe file
Enter the username, password, email address in the screen as shown below
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Currently we have to create just one user so don’t forget to check the “Only create or delete 1 user; don’t user the # of users field” Else it will create 50 users with the prefix specified in the User Prefix.
Click on Create Button and it will add the user in the aspnetdb. To check if user has been added, you can execute the following query on the table “aspnet_Users”
SELECT  [UserName]
      ,[LoweredUserName]
      ,[MobileAlias]
      ,[IsAnonymous]
      ,[LastActivityDate]
  FROM [aspnetdb].[dbo].[aspnet_Users]

Step 3: Web.config Modifications

Following changes has to be made din web.config file of the site. Open the web.config of the SharePoint site you want to change the authentication to Forms.
Add the following connection string in the <connectionStrings > part of the file.
<add name="fbaSQL" connectionString="server=localhost;database=aspnetdb;Trusted_Connection=true" />

Replace the localhost with the database server name if Databaser server is hosted on other  machine.
Replace the aspnetdb with the database name you specified in Step 1.

Add the following Lines in the <system.web> part of the file.
<membership  defaultProvider="fbaMembers">
      <providers>
        <add connectionStringName="fbaSQL" applicationName="/" name="fbaMembers" type="System.Web.Security.SqlMembershipProvider, System.Web,&#xD;&#xA;          Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
      </providers>
    </membership>

Note : Do not forget to specify the “deafultProvider” attribute in the membership tag
Add the following line inside the <PeoplePickerWildcards> tag
<PeoplePickerWildcards>
      <clear />
      <add key="AspNetSqlMembershipProvider" value="%" />
      <add key="fbaMembers" value="%" />
    </PeoplePickerWildcards>

Step 4: Add newly created user to the SharePoint site.

Go to the application and make sure that site is running in Windows authentication.
Go to the setting s page http://<Sitename>/_layouts/settings.aspx  of the site.
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Click on “Advanced Permissions” -> Click on “New” -> “Add Users”
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

It will open the Add User screen. Enter the username you created in the step 2 and click the people picker button, It will find user. Refer the image below
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Give him the required permissions and then click on Ok. Your user will be added to the sharepoint site.

Step 5: Enable the “Forms” Authentication


Open the web.config file of the site. Search for the tag “authentication”. It would be running in “Windows” authentication. Change it to “Forms” and add the <forms loginUrl="~/_layouts/login.aspx"/> in it.
Your authentication tag should look like  below
<authentication mode="Forms" >
      <forms loginUrl="~/_layouts/login.aspx"/>
    </authentication>

Step 6: Run the application

Open the site. It will redirect you to the SharePoint default login page as shown below
Change the windows authentication to Form Based authentication for SharePoint 2007 Site

Enter the required credentials and click on “Sign in”. It will redirect you to the SharePoint site with the logged in user as “Dhaval”
Change the windows authentication to Form Based authentication for SharePoint 2007 Site


Congratulations! Your site is running in the Form Based Authentication mode.
More Features:
As we are done with the basics of FBA, you can further explore more features of the FBA,
  1.  Create your own custom membership so that you can override the “ValidateUser” method to do custom validation on the SharePoint.
  2.  It is not necessary to use the separate database for Forms authentication. You can use the same existing database of your application. You just need to add the required tables in your application database. The script files can be found under %windir%\Microsoft.Net\Framework\vx.x.xxxxx of your server.

Monday, 11 April 2011

Silverlight Visual Datagrid


In my previous post I showed you how to make your own 3D chart. Here in this post I have demonstrated about making your normal Data Grid to more visual and enhanced Silverlight Datagrid.

Data Grid is generally used to retrieve the list of data in the table on the user front. Silverlight provides the flexibility to represent the data in different way that helps the end user to understand the data in more clear way and with the minimal efforts.

By default the data grid without any style looks like this.

Silverlight Visual Datagrid


By the end of this tutorial you will be able to create data grid that is more attractive and suitable for rich user interface.

Silverlight Visual Datagrid


You can easily see that both the data grids shows the same level of details but the later one is more fancy and jazzy, very suitable for the Rich UI applications.

 

Create Silverlight Application:

Open Visual studio 2008 -> File -> New Project -> select ‘Silverlight’ in Project types and Silverlight Application in Templates.
Silverlight Visual Datagrid

‘Add Silverlight Application’ box appears with two types of host to choose from.  We can either host the Silverlight content in an ASP.NET web site or to host it in a HTML web site. We will choose the first option “Add a new ASP.NET Web project to the solution to host Silverlight” and the project type as ASP.NET Web Application Project and click OK. This will create new application in IDE.
Silverlight Visual Datagrid

On Clicking ok It will create two projects
1)    VisualDataGrid –Silverlight Application which will generate .xap file
2)    VisualDataGrid.Web- To Host the .xap file generated by the previous project

Preparing the Sample Data for Data Grid:
Create a xml file called Users.xml in the VisualDataGrid project as shown below
Silverlight Visual Datagrid

Click on Add will create a Users.xml file. Paste the following contents into the file.
<?xml version="1.0" encoding="utf-8" ?>
<Users>
  <user>
    <FirstName>Roger</FirstName>
    <LastName>Fred</LastName>
    <ImagePath>../Images/Roger.JPG</ImagePath>
    <Age>30</Age>
    <Gender>Male</Gender>
    <EMail>Roger_Fred@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Sharon</FirstName>
    <LastName>Silver</LastName>
    <ImagePath>../Images/Sharon.JPG</ImagePath>
    <Age>30</Age>
    <Gender>Female</Gender>
    <EMail>Sharon_Silver@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Catherine</FirstName>
    <LastName>Zeta Jones</LastName>
    <ImagePath>../Images/Catherine.JPG</ImagePath>
    <Age>30</Age>
    <Gender>Female</Gender>
    <EMail>Catherine_Jones@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Elliot</FirstName>
    <LastName>Brunes</LastName>
    <ImagePath>../Images/Elliot.JPG</ImagePath>
    <Age>25</Age>
    <Gender>Male</Gender>
    <EMail>Elliot_Brunes@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Benjamin</FirstName>
    <LastName>Button</LastName>
    <ImagePath>../Images/Benjamin.JPG</ImagePath>
    <Age>40</Age>
    <Gender>Male</Gender>
    <EMail>Benjamin_Button@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Darren</FirstName>
    <LastName>Fredrick</LastName>
    <ImagePath>../Images/Darren.JPG</ImagePath>
    <Age>30</Age>
    <Gender>Male</Gender>
    <EMail>Darren_Fredrick@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Elton</FirstName>
    <LastName>Joseph</LastName>
    <ImagePath>../Images/Elton.JPG</ImagePath>
    <Age>30</Age>
    <Gender>Male</Gender>
    <EMail>Elton_Joseph@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Dorothy</FirstName>
    <LastName>Deborah</LastName>
    <ImagePath>../Images/Dorothy.JPG</ImagePath>
    <Age>23</Age>
    <Gender>Female</Gender>
    <EMail>Dorothy_Deborah@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Charlie</FirstName>
    <LastName>Bewley</LastName>
    <ImagePath>../Images/Charlie.JPG</ImagePath>
    <Age>23</Age>
    <Gender>Male</Gender>
    <EMail>Charlie_Bewley@infosys.com</EMail>
  </user>
  <user>
    <FirstName>Harry</FirstName>
    <LastName>Potter</LastName>
    <ImagePath>../Images/Harry.JPG</ImagePath>
    <Age>16</Age>
    <Gender>Male</Gender>
    <EMail>Harry_Potter@infosys.com</EMail>
  </user>
</Users>

Creating Data Grid:
In VisualDataGrid project it has created MainPage.xaml. This will be the default starting page of the application. Go to the design part and drag and drop the DataGrid control from the toolbox inside the xaml view of the page.


Edit the design code and change it to following
<StackPanel x:Name="LayoutRoot">
        <data:DataGrid x:Name="myDataGrid" HorizontalAlignment="Left"
                        AutoGenerateColumns="True"
FontFamily="Verdana" FontSize="11" HeadersVisibility="All"
HorizontalScrollBarVisibility="Hidden" VerticalScrollBarVisibility="Auto"
                        Width="400">
        </data:DataGrid>
</StackPanel>

Now open the source code of the file. Make the User Class in the file which will act as our source to the data grid.
public class User
{
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Age { get; set; }
        public string Gender { get; set; }
        public string ImagePath { get; set; }
        public string EMail { get; set; }

}
Now to retrieve the values from the xml we need to use the LINQ to XML. For this you need to add reference of System.xml.Linq and System.Windows.Data, using the Add Reference.
Silverlight Visual Datagrid

Silverlight Visual Datagrid


After adding the references, add the following code in the constructor of the MainPage.xaml.cs.

XDocument oDoc = XDocument.Load("Users.xml");
var myData = from info in oDoc.Descendants("user")
             select new User
            {
            FirstName = Convert.ToString(info.Element("FirstName").Value),
            LastName = Convert.ToString(info.Element("LastName").Value),
            Age = Convert.ToString(info.Element("Age").Value),
            Gender = Convert.ToString(info.Element("Gender").Value),
            ImagePath = Convert.ToString(info.Element("ImagePath").Value),
            EMail = "mailto:" + Convert.ToString(info.Element("EMail").Value)
            };
myDataGrid.ItemsSource = new PagedCollectionView(myData);

Now if you run the application using F5 it will show the output as follows
Silverlight Visual Datagrid

This is the default data grid provided by the Silverlight without any styling. Now we have to make our grid as fancy as I have showed you earlier. We are proceeding in the right direction.
First of all change the following properties of Data Grid
AutoGenerateColumns="False" HeadersVisibility="None"
As we will create our own columns and we don’t require any headers.
Now we will add our column to the data grid. We will use just one column as it solves our purpose although user is permitted to add any number of template columns in it.

<data:DataGrid.Columns>
                <data:DataGridTemplateColumn>
                    <data:DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>

                        </DataTemplate>
                    </data:DataGridTemplateColumn.CellTemplate>
                </data:DataGridTemplateColumn>
            </data:DataGrid.Columns>






Now we have to prepare the DataTemplate for our column. Clearly The layout we want for our each row has to be similar to this.
Silverlight Visual Datagrid

So we have to Create a grid with 2 Columns. First column will have only image element while the other column will have 5 StackPanels Oriented Vertically  having individual Details as shown in the figure. (These Layout changes according the different perspectives of the user)

<Grid>
<Grid.ColumnDefinitions>
            <ColumnDefinition Width="100" />
            <ColumnDefinition Width="300"/>
      </Grid.ColumnDefinitions>
      <Image Source="{Binding ImagePath}" Grid.Row="0" Grid.Column="0" Margin="10" Width="80" Height="80"/>
      <StackPanel Grid.Row="0" Grid.Column="1" Orientation="Vertical" Margin="10">
<StackPanel Orientation="Horizontal">
            <TextBlock Text="First Name : " FontWeight="Bold" />
            <TextBlock Text="{Binding FirstName}" />
</StackPanel>
      <StackPanel Orientation="Horizontal">
            <TextBlock Text="Last Name : " FontWeight="Bold" />
            <TextBlock Text="{Binding LastName}" />
</StackPanel>
      <StackPanel Orientation="Horizontal">
            <TextBlock Text="Age : " FontWeight="Bold" />
            <TextBlock Text="{Binding Age}" />
      </StackPanel>
      <StackPanel Orientation="Horizontal">
            <TextBlock Text="Gender : " FontWeight="Bold" />
            <TextBlock Text="{Binding Gender}" />
      </StackPanel>
      <StackPanel Orientation="Horizontal">
            <HyperlinkButton Content="Mail Me.." NavigateUri="{Binding EMail}" />
      </StackPanel>
      </StackPanel>
</Grid>
Also we need to add Pagination to the data grid as It takes more space than the default grid. Its good to have pagination. Silverlight provides the built in functionality to add pagination.
Drag and drop the DataPager control from the Toolbox below the DataGrid Tag.
Bind the Source of the Pager to the Itemsource of the Datagrid  directly. This automatically adds the pagination to the Datagrid.
<data:DataPager Source="{Binding Path=ItemsSource,ElementName=myDataGrid}" PageSize="5" AutoEllipsis="True" Background="#FFFFFF" Width="400" HorizontalAlignment="Left"/>
This completes the pagination as well. Now we need to have the user images located in the ClientBin/Images Folder of the VisualDataGrid.Web project.
Silverlight Visual Datagrid


Now we are ready with our custom data grid. Run the Application using F5 and it should show the output as follows.
Silverlight Visual Datagrid

This is how one can achieve the usability of the application. It is  more readable, eye catching and fancy.