Question

In my code I have a dropdown selection and upon selection from dropdown the code performs further processing and generates report/data.

Further, the entire program depends on data which is gathered from 3 different operation

Operation1: processing a text files of size of size > 6MB

Operation2: SQL Query to a DB (Query takes around 1 minute)

Operation 3: HTTP POST request to server (The main costliest part of the programe)

So, to make it efficient I am thinking to perform this operation only once and use the data for all the different selection from dropdown.

Question is how can I do so as below:

1. I can’t put it in “page_load” event because every time page loads the operations will carry out

2. I can’t put it inside “dropdownlist_selectedindexchanged” event because then it will be same as #1.

3. I thought of doing it in “page_load” as below

---

void Page_Load(object sender, EventArgs e)
{
    if(!ispostback)
    {
        Operation1();
        Operation2();
        Operation3();
    }
}

This is fine; the operations gets performed only once and I can use the data throughout, but then my page will take time to load as the operations takes time.

Is there any other way I can achieve what I want? Please let me know.

Thanks,
Rahul

Answer 1

If the data set will not change, you probably could manage to do it once at Application_Start().

Edit – something like this (typing from memory and away from VS, i do VB):

Protected void page_load(object sender, eventargs e)
{
    // the name can be anything
    if (!System.Web.HttpContext.Current.Session["data_cache_filled"])
    {
        // code to fill the cache.
        // ...

        //mark it as filled
        System.Web.HttpContext.Current.Session["data_cache_filled"] = "yes";
    }

}