Cache locking with timeout.

gistfile1.cs

private static readonly string _languagesKey = "languages";

public static Dictionary<string, string> GetLanguages()
{
    return GetData(_languagesKey, 15, () =>
    {
        // TODO: Get data from language service
        var languages = new Dictionary<string, string>();

        return languages;
    });
}

public static T GetData<T>(string dataCacheKey, int cacheTimeInMinutes, Func<T> dataMethod) where T : class
{
    var data = (T)HttpRuntime.Cache.Get(dataCacheKey);

    if (data == null)
    {
        lock (HttpRuntime.Cache)
        {
            data = (T)HttpRuntime.Cache.Get(dataCacheKey);

            if (data == null)
            {
                data = dataMethod();

                HttpRuntime.Cache.Add(dataCacheKey, data, null, DateTime.Now.AddMinutes(cacheTimeInMinutes), Cache.NoSlidingExpiration, CacheItemPriority.Normal, null);
            }
        }
    }

    return data;
}