Re: How do i empty my DataSet? - ASP.NET Discussion Boards

Re: How do i empty my DataSet?

munklefish14-Apr-06 23:45

munklefish

14-Apr-06 23:45

Jakob Lund Krarup wrote:
dataSet11.Clear();

Jakob,

How come this command has evaded me? Ive looked everywhere for something logical like this but have found no references! Even VS.Net doesnt give me any suitable response.

So much trouble for such a simple solution!!!

Thanks for the help!!!!
munklefish

Re: How do i empty my DataSet?

Jakob Farian Krarup15-Apr-06 11:00

Jakob Farian Krarup

15-Apr-06 11:00

Hi Munklefish Smile | :)

I know the feeling. It happens to us all.
There is also a Clear() method on the DataTable class, if you only want to clear a table, and not all tables in a DataSet.

You might consider storing the different tables in one dataset, and then storing the DataSet in Application, to make it easier on the database?

Kind regards - Jakob Cool | :cool:

*********************************************
Three kinds of people in the world:
- Those who can count..
- Those who can't!

10 kinds of people in the world:
- Those who understand binary
- Those who don't

Re: How do i empty my DataSet?

munklefish16-Apr-06 2:25

munklefish

16-Apr-06 2:25

Jakob Lund Krarup wrote:
You might consider storing the different tables in one dataset, and then storing the DataSet in Application, to make it easier on the database?

Jakob,

What does this involve, and how do i do it? I'm totally in this dark on this method.

Thanks!
Munklefish

Re: How do i empty my DataSet?

Jakob Farian Krarup16-Apr-06 9:18

Jakob Farian Krarup

16-Apr-06 9:18

Hi Munklefish Smile | :)

Well, now that I've looked your code over again, it seems that you fill the DataTable with very different data for each request, based on the search being done. The method I was referring to is most useful if you have a couple of tables that very seldomly change, then you can load those into Applicationstate (a piece of RAM on the webserver that is shared between all users).

It would work something along the lines of (coding from memory here - might need a bit of IntelliSense later Roll eyes | :rolleyes:

protected void LoadData()
{
  //if we don't have any data in Application
  if(Application["myData"] == null)
  {
    //then we need to load it from the database
    //so we create a fresh dataset
    dsMyData = new DataSet();

    //and a new adapter for each of the tables we want in the dataset
    SqlDataAdapter adapter = new SqlDataAdapter("SELECT * FROM orders", strConnectionString);
    //we fill the table
    adapter.Fill(sdMyData, "orders");
    //fill more tables as needed
    // .. etc ..
    // .. etc ..

    //Finally store the dataset in Application state
    Application["myData"] = dsMyData;
  }
  //otherwise, we have data in Application (from a previous call to the page)
  //and we just get a reference to the DataSet
  else
    dsMyData = (DataSet)Application["myData"];
}

This requires your connectionstring to be in the variable strConnectionString and a DataSet named csMyData to be declared on the Page level. Then you can call the LoadData method from the PageLoad eventhandler, and you will always have the tables in RAM, except for the first time of course. Application is emptied when the last users Session times out (by default 20 minutes after his/her last click on the page).

Since you actually don't need the DataTables in the code you showed me, then the DataReader is actually faster for just getting stuff from the DataBase. (also from memory ... don't hit me if it's not perfect!)

SqlConnection connection = new SqlConnection("server=(local);database=shop;user=me;password=secret");
SqlCommand command = connection.CreateCommand();
command.CommandText = "SELECT * FROM orders WHERE ...yadayadayada...";
connection.Open();
dlOrders.DataSource = command.ExecuteReader();
dlOrders.DataBind();
connection.Close();

Hope this was of some use to you.

Kind regards - Jakob Cool | :cool:

Re: How do i empty my DataSet?

munklefish16-Apr-06 9:24

munklefish

16-Apr-06 9:24

Jakob,

Very Interesting. Ill take a look at that when i have some time.

At the moment im struggling with some other stuff. (see my latest pst)

Thanks again!

Happy Easter!

Re: How do i empty my DataSet?

Jakob Farian Krarup16-Apr-06 9:27

Jakob Farian Krarup

16-Apr-06 9:27

munklefish wrote:
Happy Easter!

you too

Kind regards - Jakob Cool | :cool:

Re: How do i empty my DataSet?

munklefish15-Apr-06 0:10

munklefish

15-Apr-06 0:10

Jakob Lund Krarup wrote:
hehe .. yup - I have it on a T-shirt.......

GEEK!

Re: How do i empty my DataSet?

Jakob Farian Krarup15-Apr-06 10:58

Jakob Farian Krarup

15-Apr-06 10:58

Hehe... - yup! (and proud of it - schhh Laugh | :laugh:

)

Kind regards - Jakob Cool | :cool:

Web Reference Error???

JimFeng14-Apr-06 8:53

JimFeng

14-Apr-06 8:53

After I covert a 2005 Web Site Project to a 2005 Web Application Project, I got the following Error on a web reference which point to a web service. I removed the reference and add it again but got the same error:

Custom tool error: Unable to import WebService/Schema. Exception of type 'System.Exception' was thrown.

Any help is appreciated.

Problems losing the state with SQL Session State in a Web Farm

Albert Pascual14-Apr-06 7:26

Albert Pascual

14-Apr-06 7:26

Having a huge problem using different IIS servers and one SQL Server State. When the user goes from computer A to B the B computer quicks him out to Login again.

Any solution?

Cheers

Al

My eMail control
My Blog

Re: Problems losing the state with SQL Session State in a Web Farm

Mike Ellison14-Apr-06 10:47

Mike Ellison

14-Apr-06 10:47

Hi Al. You might need to configure the same <machineKey> on each server in the farm. Take a look at this MSDN article for the details.
How To: Configure MachineKey in ASP.NET 2.0[^]

Re: Problems losing the state with SQL Session State in a Web Farm

Albert Pascual14-Apr-06 11:01

Albert Pascual

14-Apr-06 11:01

Thanks, that's what I did. Actually you need to compile a program to generate the machinekey. Just thought that could be added into the Service State to be better solution!

I am writing my own Session State, will see how it comes out

Thanks for all your help!
Al

My eMail control
My Blog

how to display Windows form in ASP.NET 2.0

wasif_Muhammad14-Apr-06 7:18

wasif_Muhammad

14-Apr-06 7:18

My project reqiures dispalying windows forms in ASP .NET so that any type of drawing is a possible. Pls could anyone tell me how to do this?

Re: how to display Windows form in ASP.NET 2.0

Mike Ellison14-Apr-06 10:45

Mike Ellison

14-Apr-06 10:45

Here's a pretty good article that describes what you're talking about -
http://steveorr.net/articles/WinformControls.aspx[^]

AutoPostBack on a Gridview

Jason K14-Apr-06 6:58

Jason K

14-Apr-06 6:58

Hello,

I am trying to figure out how to get a textbox in a template field to autopostback. I added a text box to the item template and set the autopostback to true, and it does actually post back. However, I am trying to read information from that text box that caused the post back and I always get a null reference error. How do I make the text box content available in the TextChanged event within the Gridview? Thanks in advance.

Jason

Application_Error doesn't fire

Dario Solera14-Apr-06 5:39

Dario Solera

14-Apr-06 5:39

I have the global.asax file, generated by Visual Studio 2005, with the usual Application_Error method, that's supposed to handle all uncatched exceptions in the web application.

Well, this method is never called, even when I force a NullReferenceException intentionally.

I'm using ASP.NET 2.0.

Does anyone can help me?

___________________________________
Tozzi is right: Gaia is getting rid of us.
My Blog [ITA]

Re: Application_Error doesn't fire

Mike Ellison14-Apr-06 6:37

Mike Ellison

14-Apr-06 6:37

Hi Dario. What does your Application_Error code look like? Is it possible it is getting called, but not coded in such a way as to make that obvious?

Another possibility is if the exception is generated on a different thread than the main ASP.NET thread. Here's an article that describes it better than I can (Look about halfway down for ASP.NET specifics):
http://www.julmar.com/blog/mark/PermaLink,guid,f733e261-5d39-4ca1-be1a-c422f3cf1f1b.aspx[^]

Re: Application_Error doesn't fire

Dario Solera14-Apr-06 10:35

Dario Solera

14-Apr-06 10:35

Mike Ellison wrote:
Hi Dario. What does your Application_Error code look like?

It simply writes in a log (SQL Server) a message including the exception.

Mike Ellison wrote:
Another possibility is if the exception is generated on a different thread than the main ASP.NET thread.

I think that is the problem, because after a few tests I noticed that Application_Error has been called some times, but not all the times it should have been called.

Thanks!

___________________________________
Tozzi is right: Gaia is getting rid of us.
My Blog [ITA]

Early Page Timeout

duncanthescott14-Apr-06 4:30

duncanthescott

14-Apr-06 4:30

Looking for a little help. I have a web app that is timing out between 10 and fifteen minutes. The problem is that I have my Session State Timout set to 20 (in Web.Config) and my IIS AspSessionTimeout is set to 20 minutes.
Anyone have any ideas?

Thanks for your time and consideration,

-B

Re: Early Page Timeout

Mike Ellison14-Apr-06 6:44

Mike Ellison

14-Apr-06 6:44

Does your site use forms authentication? Is your forms authentication timeout[^] set earlier, or perhaps set with a sliding expiration?

Re: Early Page Timeout

duncanthescott14-Apr-06 8:34

duncanthescott

14-Apr-06 8:34

Thanks for the suggestion, but no I'm using:

<authentication mode="Windows">

Thanks again.

Re: Early Page Timeout

duncanthescott14-Apr-06 8:37

duncanthescott

14-Apr-06 8:37

Thanks for the suggestion Mike, but I'm using

authentication mode="Windows"

Thanks again for the suggestion.

Splitting the contents of a page on 2 printed pages

naglbitur14-Apr-06 4:22

naglbitur

14-Apr-06 4:22

Hi there.
I made an app that displays string, lines and stuff (the code is in Page_Load). I need a way to make sure that part of what is on the asp.net page gets printed on one page and part on another page. I thought that could be achieved by locating what I need way down with a high y value (above 1300) but it didn´t work. Then I tried saving the image on the hard drive and then print out but it didn´t work either, all still get´s printed out on one page (the first).
How can I control what goes on the first page and what on the second page when the contents of my page get printed out on a printer of a user that visits my page?

F

Re: Splitting the contents of a page on 2 printed pages

Mike Ellison14-Apr-06 6:12

Mike Ellison

14-Apr-06 6:12

One strategy would be to use the CSS style attribute page-break-before: always;. Here's an example of what I mean:

<html>
  <head>
    <title> Page Breaks with CSS </title>
  </head>

  <body>
    <form runat="server">
        <p>This text should print on the first page</p>
        <p style="page-break-before: always;">
            This Text should print on the second page
        </p>
    </form>
  </body>

</html>

Re: How to access a class function from Global.asax file???

Mike Ellison14-Apr-06 6:15

Mike Ellison

14-Apr-06 6:15

Is "ClassName" defined in a .vb file local to the project? Is "ClassName" part of a compiled assembly? If the latter, make sure you have added a reference to the compiled assembly in the new project.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.