can i put datatable in cache in webmethod in asp.net?

Question

User592456772 posted

what i want to do is to keep my datatable in cache so that each time my webmethod called from the ajax autocomplete extender my data table dosen't gets filled from database again and again. To be brief i dont want to interact with database everytime i press a key in textbox. can this be done? Also The Ajax autocomplete extender is working dead slow why? my code is as below:

[System.Web.Script.Services.ScriptMethod()]
    [System.Web.Services.WebMethod]
    public static List<string> GetCountries(string prefixText, int count)
    {
        DataTable dt = new DataTable();
        User objUser = new User();
        dt = objUser.GetDatatable();
 
        string Text = prefixText.ToUpper().ToString();
        List<string> LST = new List<string>();
 
         var query = from t in dt.AsEnumerable()
                     where t.Field<string>("DeptName").ToUpper().Contains(Text)
                     select new
                    {
                        DeptName = t.Field<string>("DeptName"),
 

                    };
 
         foreach (var i in query.Take(5))
         {
           LST.Add(i.DeptName.ToString().Trim());
         }
 
             return LST;
    }

an caching be done in webmethod?Thank you.

Answer 1

User-484054684 posted

Option 1: You should be able to use HttpContext.Cache
                Reference: http://forums.asp.net/t/1396653.aspx
Option 2: You can also enable server side caching of the whole output for individual WebMethods like below:
                [WebMethod(CacheDuration=60)]
                Reference: http://msdn.microsoft.com/en-us/library/y4d1bfdb(v=vs.80).aspx

Answer 2

User1508394307 posted

If list is not big and does not change every time then you can try to use cache

public static List<string> GetCountries(string prefixText, int count)
{

if (Cache["Key1"] != null) {
  return (List<string>) Cache["Key1"];

} else {

DataTable dt = new DataTable();
...
Cache.Insert("Key1", LST);
return LST;

}
}

You can also set time of expiration, etc. read more here http://msdn.microsoft.com/en-us/library/system.web.caching.cache_methods(v=vs.110).aspx

Answer 3

User-488622176 posted

• Simple : http://support.microsoft.com/kb/318299
• Other options : http://forums.asp.net/t/1746734.aspx