/// <summary>
/// RetrieveMultiple method override optimized for FetchExpression. Returns all pages using callback or 'yield' iterator
/// </summary>
/// <param name="query">A query that determines the set of record</param>
/// <param name="callback">Optional function to be called for each record page</param>
/// <returns>Entity set as 'yield' iterator</returns>
public static IEnumerable <Entity> RetrieveMultiple(this IOrganizationService service, FetchExpression query, Action <EntityCollection> callback = null)
{
CheckParam.CheckForNull(query, nameof(query));
EntityCollection collection = new EntityCollection
{
MoreRecords = true
};
/// For performance reasons it's better to load XML once
XDocument document = XDocument.Parse(query.Query);
while (collection.MoreRecords)
{
/// Paging start working if Page > 1
query.NextPage(document, collection.PagingCookie);
collection = service.RetrieveMultiple(query);
callback?.Invoke(collection);
foreach (Entity entity in collection.Entities)
{
yield return(entity);
}
}
}
public void FetchNextPage_NoPage_Test()
{
/// Setup
string expectedCookie = "<cookie page=\"1\"><accountid last=\"{ E79B8B61 - 9658 - 460F - B6B5 - A11CECF9F872}\" first=\"{ D65C4096 - B356 - 4EDB - A6C6 - A12EDA3F34EF}\" /></cookie>";
string fetch = @"<fetch count='5000' no-lock='true' >
<entity name='account' >
<attribute name='name' />
</entity>
</fetch>";
/// Act
FetchExpression query = new FetchExpression(fetch);
query.NextPage(expectedCookie);
/// Assert
XDocument document = XDocument.Parse(query.Query);
string page = document.Root.Attribute("page").Value;
string actualCookie = document.Root.Attribute("paging-cookie").Value;
Assert.AreEqual("1", page);
Assert.AreEqual(expectedCookie, actualCookie);
}