Bug [SaveProduct doesn't work] and solution for it in "Pro ASP.NET MVC 3 Framework" by Steven Sanderson, Adam Freeman

During reading "Pro ASP.NET MVC 3 Framework" by Steven Sanderson, Adam Freeman I found that my code doesn't working (Chapter 9, page 267). There is the Repository method called SaveChanges and it doesn't work for me. The code is defined like below:

public void SaveProduct(Product product) {
            if (product.ProductID == 0) {
                context.Products.Add(product);
            }
            context.SaveChanges();
        }

In order to get it working you need to change it:

public void SaveProduct(Product product)
        {
            if (product.ProductID == 0)
            {
                m_Context.Products.Add(product);
            }
            else
            {
                m_Context.Entry(product).State = System.Data.EntityState.Modified;
            }
            m_Context.SaveChanges();
        } 

Hope this would help others in learning MVC using this incredible book!

SPFile.Item => "The object specified does not belong to a list"

Today I had an SPException getting SPFile.Item with message "The object specified does not belong to a list". I used the code like this:

var web = site.RootWeb;
var file = web.GetFile("http://site.url/test/pages/page.aspx");
if (file.Exists){
   var item = file.Item;
}

And then the exception was thrown. The fix was very simple:

using (var web = site.OpenWeb("/test/pages/page.aspx", false))
var file = web.GetFile("/test/pages/page.aspx");
...
}

I'm thinking that the original exception appeared because we created SPFile object from the SPWeb which doesn't contain this file. So, seems that SPFile should be explicitly created from corresponding SPWeb.
And one more strange issue:

using (var web = site.OpenWeb("/test/pages/page.aspx", false))

opens web with server relative URL "/test" while

using (var web = site.OpenWeb("http://site.url/test/pages/page.aspx", false))

returns RootWeb :O

Unit Testing Exercises

Found 2 interesting exercises which improves the understanding of TDD, Unit Testing and Type Mocking:
Kata 1
Kata 2

P.S. Kata (型 or 形 literally: "form"?) is a Japanese word describing detailed choreographed patterns of movements practised either solo or in pairs. The term form is used for the corresponding concept in non-Japanese martial arts in general. (from http://en.wikipedia.org/wiki/Kata)

SharePoint Batch Add, Update and Delete

Recently we needed to use SharePoint Batch commands to create, update and delete items in lists. I created a simple handler which allows to easily build such queries. And you're welcome to use it.

How to use it:
Assuming we have following DTO/Model object:

public class TestListItem : IContainsId
{
public int Id { get; set; }
public string SomeText { get; set; }
public int SomeCount { get; set; }
}

And we have a list with string column "CustomSomeText" and Number column "CustomSomeCount". We could use following code to batch add/update/delete this items to list:

var items = new List<TestListItem>
{
new TestListItem{Id = 1, SomeCount = 1, SomeText ="One"},
new TestListItem{Id = 3, SomeCount = 9, SomeText ="Three"},
new TestListItem{Id = 5, SomeCount = 25, SomeText ="Twenty Five"}
};
var builder = new BatchBuilder<TestListItem>();
var fields = new[] { "CustomSomeText", "CustomSomeCount" };
var selectors = new Func<TestListItem, string>[] { x => x.SomeText, x => x.SomeCount.ToString() };
using (var site = new SPSite("http://sitecollection"))
{
var web = site.RootWeb;
var list = web.Lists["batch"];
//var command = builder.GetAddCommand(items, fields, selectors, list.ID);
//var command = builder.GetUpdateCommand(items, fields, selectors, list.ID);
var command = builder.GetDeleteCommand(items, list.ID);
string result = web.ProcessBatchData(command);
Console.WriteLine(result);
}

I think it's pretty straightforward.

IContainsId.cs

public interface IContainsId
{
    int Id { get; }
}

BatchBuilder.cs

public class BatchBuilder<T> where T : IContainsId
{
    #region Constants
    public const string BATCH_START =
        "<?xml version=\"1.0\" encoding=\"UTF-8\"?><ows:Batch OnError=\"Return\">";
    public const string BATCH_END = "</ows:Batch>";
    public const string UPDATE_COMMAND_FORMAT = "<Method ID=\"{0}\">" +
                                "<SetList>{1}</SetList>" +
                                "<SetVar Name=\"Cmd\">Save</SetVar>" +
                                "<SetVar Name=\"ID\">{2}</SetVar>{3}" +
                                "</Method>";
    public const string ADD_COMMAND_FORMAT = "<Method ID=\"{0}\">" +
                                "<SetList>{1}</SetList>" +
                                "<SetVar Name=\"Cmd\">Save</SetVar>" +
                                "<SetVar Name=\"ID\">New</SetVar>{2}" +
                                "</Method>";
    public const string DELETE_COMMAND_FORMAT = "<Method ID=\"{0}\">" +
                                "<SetList>{1}</SetList>" +
                                "<SetVar Name=\"Cmd\">Delete</SetVar>" +
                                "<SetVar Name=\"ID\">{0}</SetVar>" +
                                "</Method>";
    #endregion
    #region Public Methods
    public string GetUpdateCommand(IEnumerable<T> itemsToUpdate, string[] fieldNames, Func<T, string>[] selectors, Guid listId)
    {
        if (fieldNames.Length == 0 || selectors.Length == 0 || fieldNames.Length != selectors.Length)
        {
            throw new ArgumentException();
        }
        var batchBuilder = new StringBuilder(BATCH_START);
        foreach (var itemToUpdate in itemsToUpdate)
        {
            var id = itemToUpdate.Id;
            var fieldsBuilder =
                fieldNames.Select(
                    (x, i) => string.Format("<SetVar Name=\"urn:schemas-microsoft-com:office:office#{0}\">{1}</SetVar>", x, selectors[i].Invoke(itemToUpdate)))
                    .Aggregate(new StringBuilder(), (c, n) => c.Append(n));
            batchBuilder.AppendFormat(UPDATE_COMMAND_FORMAT, id, listId, id, fieldsBuilder);
        }
        batchBuilder.Append(BATCH_END);
        return batchBuilder.ToString();
    }
    public string GetAddCommand(IEnumerable<T> itemsToAdd, string[] fieldNames, Func<T, string>[] selectors, Guid listId)
    {
        if (fieldNames.Length == 0 || selectors.Length == 0 || fieldNames.Length != selectors.Length)
        {
            throw new ArgumentException();
        }
        var batchBuilder = new StringBuilder(BATCH_START);
        var methodId = 1;
        foreach (var itemToAdd in itemsToAdd)
        {
            var fieldsBuilder =
                fieldNames.Select(
                    (x, i) => string.Format("<SetVar Name=\"urn:schemas-microsoft-com:office:office#{0}\">{1}</SetVar>", x, selectors[i].Invoke(itemToAdd)))
                    .Aggregate(new StringBuilder(), (c, n) => c.Append(n));
            batchBuilder.AppendFormat(ADD_COMMAND_FORMAT, methodId, listId, fieldsBuilder);
            ++methodId;
        }
        batchBuilder.Append(BATCH_END);
        return batchBuilder.ToString();
    }
    public string GetDeleteCommand(IEnumerable<T> itemsToDelete, Guid listId)
    {
        var batchBuilder = new StringBuilder(BATCH_START);
        foreach (var itemToDelete in itemsToDelete)
        {
            batchBuilder.AppendFormat(DELETE_COMMAND_FORMAT, itemToDelete.Id, listId);
        }
        batchBuilder.Append(BATCH_END);
        return batchBuilder.ToString();
    }
    #endregion
}

List Event Receiver and Feature Scope

Recently my colleague created an event receiver which was going to be instantiated for all picture libraries at the site collection. He created a receiver and bound it like this:

<?xml version="1.0" encoding="utf-8"?>
<Elements xmlns="http://schemas.microsoft.com/sharepoint/">
  <Receivers ListTemplateId="109">
      <Receiver>
        <Name>PictureLibraryEventReceiverItemUpdating</Name>
        <Type>ItemUpdating</Type>
        <Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
        <Class>Company.Features.PictureLibraryEventReceiver</Class>
        <SequenceNumber>10008</SequenceNumber>
      </Receiver>
      <Receiver>
        <Name>PictureLibraryEventReceiverItemDeleting</Name>
        <Type>ItemDeleting</Type>
        <Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
        <Class>Company.Features.PictureLibraryEventReceiver</Class>
        <SequenceNumber>10009</SequenceNumber>
      </Receiver>
  </Receivers>
  <Receivers ListTemplateId="851">
    <Receiver>
      <Name>PictureLibraryEventReceiverItemUpdating</Name>
      <Type>ItemUpdating</Type>
      <Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
      <Class>Company.Features.PictureLibraryEventReceiver</Class>
      <SequenceNumber>10010</SequenceNumber>
    </Receiver>
    <Receiver>
      <Name>PictureLibraryEventReceiverItemDeleting</Name>
      <Type>ItemDeleting</Type>
      <Assembly>$SharePoint.Project.AssemblyFullName$</Assembly>
      <Class>Company.Features.PictureLibraryEventReceiver</Class>
      <SequenceNumber>10011</SequenceNumber>
    </Receiver>
  </Receivers>
</Elements>

Unfortunately, it turned out that SharePoint (2010) added this receivers to all lists and libraries ignoring ListTemplateId parameter. I started investigating what's wrong and expected that my colleague made a mistake.

I noticed that feature scope is Site which is kind of logical since we're going to use this receiver in subsites as well. So, here starts an interesting part. I found out that MOSS 2010 uses following behavior:

1. If feature scope is site
1. If receiver scope is set to site = provision receiver to all lists of site collection (list template/url is not taken into consideration)!
2. If receiver scope is set to web = provision receiver to all lists of the particular web (list template/url is not taken into consideration)!
2. If feature scope is web
1. If list template and list url are not set = 1.1
2. List template = provision to all lists of correct type
3. List url = provision receiver to the particular list