1. New SharePoint APIs – The new UI framework has more extensibility in the ribbon and natively uses XSLT DataViews in lists vs. previous CAML views. There are new APIs for AJAX and Silverlight applications that make it make it much easier to access SharePoint data with less code and better performance. Improved list access and programmability with REST, ATOM, JSON and LINQ including richer data relationship, validation, joins and projections over SharePoint lists.

2. Application Lifecycle – WSP as the packaging and deployment format for SharePoint solutions. You can save as WSP in SPD and bring that into Visual Studio 2010.

3. Visual Studio 2010 Support – SharePoint 2010 is a first class target for Visual Studio 2010. This includes F5 deployment and debugging as well as designers for various SharePoint project types, web parts, workflow, business connectivity services and integration with the VS Server Explorer. The early feedback on this has been so great, we decided to highlight it in Steve Ballmer's keynote at the SharePoint Conference.

4. Developer Dashboard View – If you have the rights, you can turn on a mode for a SharePoint page which will render at the bottom to show full trace and latency through the SharePoint, .NET and SQL layers. You can use reporting tools described earlier to identify any slow pages in your site and then turn on this view to see a custom web part has bogged down the page by making repeated expensive SharePoint object model calls.

5. Development on Windows 7 – Development on Windows 7 and Vista client machines supported. Although it isn’t a supported configuration for production.

Reference : http://blogs.msdn.com/sharepoint/archive/2009/10/19/sharepoint-2010.aspx

SPContext.Current.Web.AllowUnsafeUpdates = true;
SPWebCollection webs = SPContext.Current.Web.Webs;
objWebs.Add("Sample Site", "Sample Site", "This is the Sample Site", 1033,"STS#0", true, false);
SPContext.Current.Web.AllowUnsafeUpdates = false;

SPWeb mySite = SPContext.Current.Web;
SPListCollection lists = mySite.Lists;

string listTitle = TextBox1.Text;
string listDescription = TextBox2.Text;
string listType = ListBox1.SelectedItem.Text;

SPListTemplateType listTemplateType = new SPListTemplateType();

switch(listType)
{
    case "Generic List":
    {
        listTemplateType = SPListTemplateType.GenericList;
        break;
    }

    case "Events":
    {
        listTemplateType = SPListTemplateType.Events;
        break;
    }

    case "Announcements":
    {
        listTemplateType = SPListTemplateType.Announcements;
        break;
    }
}

lists.Add(listTitle, listDescription, listTemplateType);

namespace  DataViewer

{

     public   class   DataView  :  WebPart

     {

         Button  btn;

         GridView  gv;

         protected   override void  CreateChildControls()

        {

            btn =  new  Button();

            btn.Text =  "Data Getir" ;

            btn.Click +=  new EventHandler(btn_DataGetir);

            gv =  new   GridView ();

            this.Controls.Add(btn);

            this.Controls.Add( new   LiteralControl ( "<br>" ));

            this.Controls.Add(gv);

        }

         public   void btn_DataGetir( object  sender,  EventArgs  e)

        {

            DataSet  ds = getData();

            gv.DataSource = ds.Tables[0];

            gv.DataBind();

        }

         public   DataSet getData()

        {

            DataSet  ds =  new DataSet ();

            DataTable  dt =  new   DataTable ();

            dt.Columns.Add( "Alan1" , Type.GetType( "System.String" ));

            dt.Columns.Add( "Alan2" , Type.GetType( "System.String" ));

            dt.Columns.Add( "Alan3" , Type.GetType( "System.String" ));

            DataRow dr;

            for  ( int i = 0; i < 10; i++)

            {

                dr = dt.NewRow();

                dr["Alan1"] =  "TestVeriA"  + i;

                dr["Alan2"] =  "TestVeriB"  + i;

                dr["Alan3"] =  "TestVeriC"  + i;

                dt.Rows.Add(dr);

            }

            ds.Tables.Add(dt);

            return  ds;

        }

     }

}

using  System;

using  System.Collections.Generic;

using  System.Text;

using  System.Web.UI;

using  System.Web.UI.WebControls;

using  System.Web.UI.WebControls.WebParts;

namespace  SimpleCalculator

{

     public   class   Calculator :  WebPart

     {

         TextBox tbA;

         TextBox tbB;

         TextBox tbResult;

         Button btnAdd;

         Button btnSub;

         protected override   void CreateChildControls()

        {

            base.CreateChildControls();

            EnsurePanelFix();

              UpdatePanel  refreshCalculation =  new   UpdatePanel ();

            ScriptManager scriptHandler =  new   ScriptManager ();

            tbA =  new   TextBox ();

            tbB =  new   TextBox ();

            tbResult =  new   TextBox ();

            btnAdd =  new   Button ();

            btnSub =  new   Button ();

            tbResult.ReadOnly =  true ;

            btnAdd.Text =  "+" ;

            btnSub.Text =  "-" ;

        scriptHandler.ID =  "scriptHandler" ;

        refreshCalculation.ID =  "refreshName" ;

        refreshCalculation.UpdateMode = UpdatePanelUpdateMode.Always;

        refreshCalculation.ChildrenAsTriggers =  true ;

        btnAdd.Click +=  new   EventHandler (btnAdd_Click);

        btnSub.Click +=  new   EventHandler (btnSub_Click);

        refreshCalculation.ContentTemplateContainer.Controls.Add(tbA);

        refreshCalculation.ContentTemplateContainer.Controls.Add(newLiteralControl( "<br>" ));

        refreshCalculation.ContentTemplateContainer.Controls.Add(tbB);

        refreshCalculation.ContentTemplateContainer.Controls.Add(newLiteralControl( "<br>" ));

        refreshCalculation.ContentTemplateContainer.Controls.Add(btnAdd);

        refreshCalculation.ContentTemplateContainer.Controls.Add(btnSub);

        refreshCalculation.ContentTemplateContainer.Controls.Add(newLiteralControl( "<br>" ));

        refreshCalculation.ContentTemplateContainer.Controls.Add(tbResult);

        this .Controls.Add(scriptHandler);

        this .Controls.Add(refreshCalculation);

        }

         void  btnAdd_Click( object sender,  EventArgs e)

        {

            int  a =  int .Parse(tbA.Text);

              int  b=  int .Parse(tbB.Text);

            int  c = a + b;

            tbResult.Text = c.ToString();

        }

         void  btnSub_Click( object sender,  EventArgs e)

        {

            int  a =  int .Parse(tbA.Text);

            int  b =  int .Parse(tbB.Text);

            int  c = a - b;

            tbResult.Text = c.ToString();

        }

         private   void EnsurePanelFix()

        {

            if  ( this .Page.Form!=  null )

            {

                String fixupScript =  @"

             _spBodyOnLoadFunctionNames.push(""_initFormActionAjax"");

              function_initFormActionAjax()

              {

                if(_spEscapedFormAction == document.forms[0].action)

                {

                 document.forms[0]._initialAction =

                 document.forms[0].action;

                }

              }

              varRestoreToOriginalFormActionCore =

               RestoreToOriginalFormAction;

             RestoreToOriginalFormAction = function()

              {

                if(_spOriginalFormAction != null)

                {

                 RestoreToOriginalFormActionCore();

                 document.forms[0]._initialAction =

                   document.forms[0].action;

                }

              }" ;

                  ScriptManager .RegisterStartupScript( this ,

                   typeof ( Calculator ), "UpdatePanelFixup" ,

                   "_spOriginalFormAction =document.forms[0].action; _spSuppressFormOnSubmitWrapper=true;" ,  true );

            }

        }

     }

}

In Sharepoint development we can easly read data in normal field types. Exp : Single Line of Text, Numeric, Choose, etc. But in a Person or Group field we have some problems. Because this field type stores an xml based data that includes username, domain name, user profile page url, etc. If you want to read only username data in this kind of field you must use different ways to read it.

string fieldValue = item["AssignedTo"].ToString();
SPFieldUserValue assignedTo = new SPFieldUserValue(site.AllWebs[<Your_Site>], fieldValue);
string assignedToUserName = assignedTo.User.LoginName;

SharePoint list views don't contain SPListItems or SPListItemCollections, if you want to programmatically retrieve list items from a list in the order specified by a view you've created you have to do it as follows : 

SPListItemCollection items = spWeb.Lists["ListName"].GetItems(spWebInstance.Lists["ListName"].Views ["ViewName"]);  

If you want to add user's profile pictures to your existing Sharepoint application, you must add all photos to a picture library and then relate it to users profiles. If you want to do this via code you can use the following. 

 Code written by Mesut Gurbuz (Software Consultant) 

user.Commit();