Performing Cross-List Queries in SharePoint 2010 using Visual Studio and Cross Site look up

Try creating tasks in several sites within the site collection, assign them to your own account then run this project.

This SPSiteDataQuery searches for all entries in all Tasks folders that are assigned to the current

Steps

• Open Visual Studio in your system.
• Select Console Application template and give as name.
• Add a Microsoft.Client Assembly reference file in right side reference tab in visual studio.
• Replace Program.cs with the source code.

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;
using Microsoft.SharePoint;

namespace GENERAL_CrossListQuery
{
    class Program
    {

        static void Main(string[] args)
        {
            //Start by formulating the query in CAML

            SPSiteDataQuery query = new SPSiteDataQuery();

            //Get IDs for the SharePoint built-in fields we want to use
            string assignedToID = SPBuiltInFieldId.AssignedTo.ToString("B");
            string taskDueDateID = SPBuiltInFieldId.TaskDueDate.ToString("B");
            string titleID = SPBuiltInFieldId.Title.ToString("B");
            string taskStatusID = SPBuiltInFieldId.TaskStatus.ToString("B");
            string percentCompleteID = SPBuiltInFieldId.PercentComplete.ToString("B");

            //This is the selection creterion
            string whereClause = "<Where><Eq><FieldRef ID='" + assignedToID + "' />"
                + "<Value Type='Integer'><UserID/></Value>"
                + "</Eq></Where>";

            //This is the sort order
            string orderByClause = "<OrderBy><FieldRef ID='" + taskDueDateID + "' /></OrderBy>";

            //Set the query CAML
            query.Query = whereClause + orderByClause;

            //We will query all the Tasks lists
            query.Lists = "<Lists ServerTemplate='107' />";

            //Define the view fields in the result set
            string viewFields = "<FieldRef ID='" + titleID + "' />"
                + "<FieldRef ID='" + taskDueDateID + "' Nullable='TRUE' />"
                + "<FieldRef ID='" + taskStatusID + "' Nullable='TRUE' />"
                + "<FieldRef ID='" + percentCompleteID + "' Nullable='TRUE' />";
            query.ViewFields = viewFields;

            //Query all the SPWebs in this SPSite
            query.Webs = "<Webs Scope='SiteCollection'>";

            //Get the SPSite and SPWeb, ensuring correct disposal
            //Replace the URL with your own site collection
            using (SPSite site = new SPSite("http://intranet.contoso.com/"))
            {

                using (SPWeb web = site.OpenWeb())
                {

                     //Run the query
                    DataTable resultsTable = web.GetSiteData(query);

                    //Print a heading line
                    Console.WriteLine("{0, -10} {1, -30} {2, -20} {3}", "Date Due", "Task", "Status", "% Complete");

                    //Loop through the results and print them
                    foreach (DataRow currentRow in resultsTable.Rows)
                    {
                        //Extract various values
                        string dueDate = (string)currentRow[taskDueDateID];
                        string task = (string)currentRow[titleID];
                        string status = (string)currentRow[taskStatusID];
                        string percentComplete = (string)currentRow[percentCompleteID];

                        //Format the due date
                        DateTime dueDateTime;
                        bool hasDate = DateTime.TryParse(dueDate, out dueDateTime);
                        if (hasDate)
                        {
                            dueDate = dueDateTime.ToShortDateString();
                        }
                        else
                        {
                            dueDate = String.Empty;
                        }

                        //Format the percent complete string
                        decimal pctDec;
                        bool hasValue = decimal.TryParse(percentComplete, out pctDec);
                        if (hasValue)
                        {
                            percentComplete = pctDec.ToString("P0");
                        }
                        else
                        {
                            percentComplete = "0%";
                        }

                        //Print a line for this row
                        Console.WriteLine("{0, -10} {1, -30} {2, -20} {3, 10}", dueDate, task, status, percentComplete);

                    }

                }

            }
            //Wait for the user to press a key before closing
            Console.ReadKey();

        }
    }
}