Example of a custom data source for Visual Studio Webtests

AnnotationsDataSource.cs

using System;
using System.Data;
using System.Data.SqlClient;

namespace Hudl.WebApp.Tests.TestsCore.DataSources
{
    public class AnnotationsDataSource : ModifiableQueueBasedDataSource<long>
    {
        private readonly long _userId;

        public AnnotationsDataSource(long userId)
        {
            _userId = userId;
            HasBeenModified = false;
        }

        protected override void LoadItems()
        {
            const string annotationDataQuery = @"SELECT [AnnotationId]
                                                 FROM [AnnotationData] 
                                                 WHERE [UserId] = @UserId";
            var sqlCommand = new SqlCommand(annotationDataQuery);
            sqlCommand.Parameters.Add("@UserId", SqlDbType.BigInt).Value = _userId;

            UsingDataReader(sqlCommand, EnqueueAnnotationData);
        }

        private void EnqueueAnnotationData(SqlDataReader sqlDataReader)
        {
            var annotationId = Convert.ToInt64(sqlDataReader["AnnotationId"]);

            DataItems.Enqueue(annotationId);
        }

        public override string ToString()
        {
            var value = String.Format("AnnotationsDataSource: Is loaded: {0}, {1} items, User {2}, Has been modified: {3}", IsLoaded, DataItems.Count, _userId, HasBeenModified);
            return value;
        }
    }
}