write datable to memory stream... cant read from stream

Hi Guys,

I have built a website that allows user to upload csv file to datatable.  Maybe I don't quite understand the purpose of memory stream.

I write to stream by the below code


thanks!!

public partial class _Default : System.Web.UI.Page
{

    DataTable table;
    DataTable table2;
    protected DataTable dtable;
    MemoryStream memStm = new MemoryStream();

    protected void Unnamed2_Click(object sender, EventArgs e)
    {
...create table here
        table.AcceptChanges();

        GridView1.DataSource = table;
        GridView1.DataBind();

        table.WriteXml(memStm,XmlWriteMode.WriteSchema);
        memStm.Seek(0, System.IO.SeekOrigin.Begin);
}}

Open in new window



then in a new section

    protected void Button1_Click(object sender, EventArgs e) //launch program
    {

        DataTable newTable = new DataTable();
        memStm.Seek(0, System.IO.SeekOrigin.Begin);
        newTable.ReadXml(memStm);

        GridView2.DataSource = newTable;
        GridView2.DataBind();

Open in new window



I thought when I wrote to memory, I could always access it, any ideas what I'm doing wrong?

thanks
solarissfAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

BuggyCoderCommented:
because its an asp.net page, every request will be handled by fresh instance of Default page handler.
for you to save datatable to be used across your page postbacks, just save it in session as:-

protected void Unnamed2_Click(object sender, EventArgs e)
    {
...create table here
        table.AcceptChanges();

        GridView1.DataSource = table;
        GridView1.DataBind();

        Session["table"]=table;
}

protected void Button1_Click(object sender, EventArgs e) //launch program
    {

        DataTable newTable = Session["table"] as DataTable;

        GridView2.DataSource = newTable;
        GridView2.DataBind();
}
0
solarissfAuthor Commented:
I was told that if I save in session, once the table gets huge, which it will, user performance will suffer and the page will take forever to load.  Is this true?
0
BuggyCoderCommented:
in that case i think you should go for jquery ui and get the data using ajax and bind it on client side.
by doing so you can only fetch the data that is new and append it on client side....
0
Cloud Class® Course: C++ 11 Fundamentals

This course will introduce you to C++ 11 and teach you about syntax fundamentals.

solarissfAuthor Commented:
sorry, above my knowledge spectrum.  Before I get into learning that method, what if I write the xml to the actual server, then delete it at end of method?

I didn't want to do that at first though.  What are the benefits/drawbacks from using your method vs writing to server?

thanks
0
BuggyCoderCommented:
in case of xml you have to save as many xml files as number of requests to your page.
then you should know which xml to bind to which user.

That's practically impossible, if your datatable has less than say 1000 rows, go for session, otherwise jquery/ajax...

you can also use paging in gridview to limited number of data from from datatable to your markup....

Remember, session data doesn't travel back to client, it remains in IIS Memory only.....
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
solarissfAuthor Commented:
thank you very much,,this cleared up alot.
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
ASP.NET

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.