Tridion Broker Query

In this blog post I am going to show you how you can easily create a broker query with various kinds of criteria specified. I will be using Tridion 2013 and Visual Studio 2010 in this case.

In my example I have a .NET user control, which is placed inside a Frontend project. Its goal is to list all the components from Tridion that are using a certain schema.

First of all, let’s start with the user control. Here is how mine looks like:

ucListItems.ascx

	<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="ucListItems.ascx.cs" Inherits="Yabolka.BrokerQuery.Frontend.inc.ucListItems" %>
	<ul>
	<asp:Repeater runat="server" ID="repeaterListItems">
	<ItemTemplate>
	<%# Container.DataItem %>
	</ItemTemplate>
	</asp:Repeater>
	</ul>

view raw ucListItems.ascx hosted with ❤ by GitHub

We create an unordered list and inside of it, is where the magic is going to happen. There we make a Repeater which will bind all the results from the query. These are going to be returned as list items, containing all the information, with the help of a Component Template.

Now let’s go to the code behind of this control and start with the main implementation that is the topic of the blog post. I am explaining everything with comments inside the code block bellow:

ucLatestNews.ascx.cs

	using System;
	using System.Collections.Generic;
	using System.Linq;
	using System.Web;
	using System.Web.UI;
	using System.Web.UI.WebControls;
	using Tridion.ContentDelivery.DynamicContent.Query;
	using Tridion.ContentDelivery.DynamicContent;
	namespace Yabolka.BrokerQuery.Frontend.inc
	{
	public partial class ucListItems : System.Web.UI.UserControl
	{
	//The id of the component template that we are going to use.
	//We have hardcoded the id of the component template for this example.
	public string TemplateId = "tcm:6-214-32";
	protected void Page_Load(object sender, EventArgs e)
	{
	if (!Page.IsPostBack)
	{
	BindItems();
	}
	}
	protected void BindItems()
	{
	//We create a list of strings which will be the data source of our repeater.
	List<string> itemsList = new List<string>();
	try
	{
	//Here is our first criteria - ItemSchemaCriteria. Here we say to the query that we need all the items with the specified schema id.
	//We have hardcoded the id of the schema for this example.
	ItemSchemaCriteria schemaCriteria = new ItemSchemaCriteria(26);
	//We might also want to make a Type criteria. For example, "Is the item type 'Component'?" criteria.
	//However, we've already set a schema criteria and this means that we will only have items of type Component returned.
	//But we may need the ItemTypeCriteria for other purposes.
	//We have hardcoded the id of the type for this example.
	ItemTypeCriteria typeCriteria = new ItemTypeCriteria(16);
	//We might want to specify the publication as well. For doing so, we can use the PublicationCriteria.
	//We have hardcoded the id of the publication for this example.
	PublicationCriteria publicationCriteria = new PublicationCriteria(6);
	//If we need to specify a limit of the listed items, we may use LimitFilter. In this case we want 4 items to be displayed so we set the parameter to 4.
	LimitFilter limitFilter = new LimitFilter(4);
	//We create a list of Criteria and add the criteria we specified above to this list.
	List<Criteria> allCriteria = new List<Criteria>();
	allCriteria.Add(schemaCriteria);
	allCriteria.Add(typeCriteria);
	allCriteria.Add(publicationCriteria);
	//If we need to sort our results (for example if we want to display the latest items, then we can sort the results by date)
	//we can use a SortParameter. In this case we take the value of a Metadata Field called "Date" and we sort the results by it.
	//CustomMetaKeyColumn customMetaKeyColumnDate = new CustomMetaKeyColumn("Date", MetadataType.DATE);
	//SortParameter sortParameter = new SortParameter(customMetaKeyColumnDate, SortParameter.Descending);
	//Create the query.
	Query QueryNews = new Query();
	//Add all criteria.
	QueryNews.Criteria = CriteriaFactory.And(allCriteria.ToArray());
	//Set the limit filter.
	QueryNews.SetResultFilter(limitFilter);
	//If we have a sorting parameter we can add it like this.
	//QueryNews.AddSorting(sortParameter);
	//Execute the query.
	String[] ItemResultsNews = QueryNews.ExecuteQuery();
	//Go through the query result entries.
	foreach (String news in ItemResultsNews)
	{
	//Get the component presentation
	ComponentPresentationAssembler ass = new ComponentPresentationAssembler();
	//Get the content of the component presentation
	string content = ass.GetContent(news, TemplateId);
	//Add the content to the data source of the repeater
	itemsList.Add(content);
	}
	if (this.FindControl("repeaterListItems") != null)
	{
	//Set the repeater's data source and bind the data
	repeaterListItems.DataSource = itemsList;
	repeaterListItems.DataBind();
	}
	}
	catch (Exception ex)
	{
	//TODO: Add error logging
	}
	}
	}
	}

view raw ucListItems.ascx.cs hosted with ❤ by GitHub

That’s it! Now we are ready to get all the components with schema, which we specified by its id, and display these as we wish. You can go on and give it a try.

Please, don't forget to:

• add the user control to a page where you want to display the components
• make sure that the components are published
• make sure you have the right Tridion DLLs (netrtsn, Tridion.ContentDelivery.Configuration, Tridion.ContentDelivery, Tridion.ContentDelivery.Interop, xmogrt). It is imporant to have these in 32-bit or 64-bit depending on your project
• make sure you have all the JARs from Tridion
• make sure you have configured correctly the config files of Tridion

I hope you like the article and find it useful and interesting. If you have any questions, please do not hesitate to contact me.