Google API

Querying Youtube API using C#

Posted in .NET 2.0 | Google API | YouTube at Thursday, December 20, 2007 10:40 PM UTC

This example shows how to use Google Data API to query and obtain videos from YouTube. There is also a downloadable zip file with the example in ASP.NET / C#.

First of all, you need to download the Google Data APIs Client Libraries.
Second, use the following namespaces:

using Google.GData.Client;
using Google.GData.Extensions;

Use the service by querying by tag, or by search (you can also query related items, etc..):

    //by tag
    //feel free to change number of items, by there is a limit of 50, I believe. 
    //If you want to retreive more, you have to do a loop (retrieve 1-50, then 51 to 100, etc)
    protected void btoGo_Click(object sender, EventArgs e)
    {
        string url = "http://gdata.youtube.com/feeds/videos/-/" + this.txtTag.Text;
        AtomFeed myFeed = GetFeed(url, 1, 20);
        DisplayFeed(myFeed);        
    }

    //by search
    //feel free to change number of items, by there is a limit of 50, I believe. 
    //If you want to retreive more, you have to do a loop (retrieve 1-50, then 51 to 100, etc)
    protected void btoSearch_Click(object sender, EventArgs e)
    {
        string url = "http://gdata.youtube.com/feeds/videos?q=" + this.txtSearch.Text;
        AtomFeed myFeed = GetFeed(url, 1, 15);
        DisplayFeed(myFeed);
    }

Use the following methods, or similars to get and display the Feed:

    /// <summary>
    /// Create and returns and Google.GData.Client.AtomFee from url with the specific start and number of items
    /// </summary>
    /// <param name="url"></param>
    /// <param name="start"></param>
    /// <param name="number"></param>
    /// <returns></returns>
    private static AtomFeed GetFeed(string url, int start, int number)
    {
        System.Diagnostics.Trace.Write("Conectando youtube at " + url);
        FeedQuery query = new FeedQuery("");
        Service service = new Service("youtube", "exampleCo");
        query.Uri = new Uri(url);
        query.StartIndex = start;
        query.NumberToRetrieve = number;

        AtomFeed myFeed = service.Query(query);
        return myFeed;
    }

    /// <summary>
    /// Renders feed in example aspx page
    /// </summary>
    /// <param name="myFeed"></param>
    private void DisplayFeed(AtomFeed myFeed)
    {
        System.Text.StringBuilder sb = new System.Text.StringBuilder();
        foreach (AtomEntry entry in myFeed.Entries)
        {
            #region render each
            sb.Append("<br /><b>Title:</b> ");
            sb.Append(entry.Title.Text);
            sb.Append("<br /><b>Categories:</b> ");
            foreach (AtomCategory cat in entry.Categories)
            {
                sb.Append(cat.Term);
                sb.Append(",");
            }
            sb.Append(RenderVideoEmbedded(getIDSimple(entry.Id.AbsoluteUri)));
            sb.Append("<br /><b>Published on:</b> ");
            sb.Append(entry.Published);
            #endregion
        }
        this.lblResults.Text = sb.ToString();
    }



    private string RenderVideoEmbedded(string idSimple)
    {
        return string.Format("<div id=\"video{0}\"><object width=\"425\" height=\"355\"><param name=\"movie\" value=\"http://www.youtube.com/v/{0}&rel=1\"></param><param name=\"wmode\" value=\"transparent\"></param><embed src=\"http://www.youtube.com/v/{0}&rel=1\" type=\"application/x-shockwave-flash\" wmode=\"transparent\" width=\"425\" height=\"355\"></embed></object></div>", idSimple);
    }