ASP.NET Cache dependency example

In this article we will learn how to implement file dependency in caching.

In this method the cache["messageDependency"]  loads the file "DependencyFile.txt" in memory(cache) only when its content is changed in the disk.

public void displayMessage()

{

         String message;

         String Path = "~/DependencyFile.txt";

         if (Cache["messageDependency"] == null)

         {

                  System.IO.StreamReader sReader = new StreamReader(Server.MapPath(Path));

                  message = sReader.ReadToEnd();

                  sReader.Close();

                  System.Web.Caching.CacheDependency msgDependency = new System.Web.Caching.CacheDependency(Server.MapPath(Path));

                  Cache.Insert("messageDependency", message, msgDependency);

         }

         Response.Write(Cache["messageDependency"].ToString());

}