JQuery + ASP.NET auto complete without web service

Ever thought of creating an auto complete that interact with Database/Data source in ASP.NET and wonder how you going to do it? Well, the answer is simple, you need a web service, right? Wrong!

In this article, I will explain how to create auto complete functionality in ASP.NET JQuery without using a web service.

First, let's make a list of things we are going to use:
1. Jquery Library
2. XML File(Data source)
3. ASP.NET Page

Let's get started.

In Visual Studio, create a web site/ web Application and then create two folders to put the JQuery Library and Css files. Create .aspx file and then add the code in the code behind. All I do in this code is simply read the XML file and then load it to the dataset (you can use xPath to manipulate xml data, I just happen to prefer using dataset.)
Here is my Code:

protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            XmlDocument xDoc = new XmlDocument();
            xDoc.Load(Server.MapPath("Data/Customers.xml"));
            DataSet ds = new DataSet();
            XmlNodeReader xnr = new XmlNodeReader(xDoc);
            ds.ReadXml(xnr);
            foreach (DataRow _row in ds.Tables["Customers"].Rows)
            {
                ClientScript.RegisterArrayDeclaration("ListItems", "\"" + _row["ContactName"].ToString() + "\"");
            }
        }
    }

This is a simple straight forward code, but it's important to note the Clientscript.RegisterArrayDeclaration which creates a JavaScript Array. We then Access the Array using Jquery like this:

$(function () {
           $("#tags").autocomplete({
               source: ListItems
           });
       });

Just few things I need to explain.

1. Autocomplete expects an Array, so we create this in C#, so you can replace the XML with your Database source and you will be able to create an Array for the Autocomplete.
   
2. The Array name is the name you passed in the

   ClientScript.RegisterArrayDeclaration

   
   
   It must exist in runtime for you code to execute correctly.
   

Now your Autocomplete should be working!

Please feel free to correct me where I am wrong as I am still learning....