ASP.NET

Viewstate not updated after TransmitFile

23-Jul-10 4:29

My Pleasure.

Jinal Desai - LIVE
Experience is mother of sage....

KittyKit22-Jul-10 10:53

KittyKit

22-Jul-10 10:53

Hello there

I have been spending almost half-a-day to get this problem solved, but could not even find a single article that would help me. I wonder whether nobody else has faced this problem.

Okay, my webpage involves creating excel files. My download button has code like this

HttpContext.Current.Response.Clear();
HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=clientcopy.xlsx");
HttpContext.Current.Response.TransmitFile(Server.MapPath("App_data/" + Viewstate["FileName"]));
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.Close();
HttpContext.Current.Response.End();

Alright. this works fine. The problem is, After downloading I want to make Viewstate["FileName"] to be null. But whatever I do, during the next post back after the filetransmit, the Viewstate["FileName"] still retains the old value and refuses to get updated to null. I tried writing the Viewstate["FileName"] = null; at every possible place in the above code - at the begining, in the middle and at the end after response.end(). BUT no way Cry | :((

Can someone help on how to modify the viewstate after a file transmit???

Note:
=====
My webpage has an update panel. Button "GO" displays a report in the update panel based on some selections outside the updatepanel. Button "ADD" keeps on adding the displayed reports to an excelfile until Button "download" is clicked and excelfile is downloaded. "GO" and "ADD" triggers partial postback and "download" triggers fullpostback.

thanks
Kit

Yusuf22-Jul-10 13:52

22-Jul-10 13:52

You may want to read this msdn[^] article about view states.

You may have to override the SaveViewState() method on the page and set the value to null. Don't forget to call the base.SaveViewState() through!

Yusuf
May I help you?

Prosanta Kundu online22-Jul-10 19:54

Prosanta Kundu online

22-Jul-10 19:54

Try this

HttpContext.Current.Response.TransmitFile(Server.MapPath("App_data/" + Viewstate["FileName"]));
Viewstate["FileName"] = "";
HttpContext.Current.Response.Flush();

T M Gray23-Jul-10 8:44

T M Gray

23-Jul-10 8:44

ViewState is the state of the "View", or in other words the state of the page displayed in the browser. Since the transmission of the file doesn't change that view it wouldn't change the ViewState. If you want something that can be changed with the file transmission you need to use a data location that can be affected by it. I suggest setting a cookie.

HTML Print of Selected Tab using RenderControl Method

KittyKit24-Jul-10 2:32

KittyKit

24-Jul-10 2:32

Thanks for the replies, guys.

@Yusuf: The link seems to be really good and informative. will go thro it. thanks. As a quick try, I tried overriding the SaveViewstate function. But that didnt help.
@Prosanta: It didnt work either. As I mentioned earlier I had placed the code at every possible location
@Gray: I think i will try storing it in the session. What say?

Cheers
Kit

NTheOne21-Jul-10 21:17

NTheOne

21-Jul-10 21:17

Hi To All,

Can anybody help me how to print the selected tab in the Ajax tab container in HTML format?

On Button click I have to print the selected tab in HTML format.
So I have written one method for that.

public void RenderControl(Control ctrl)
{   
StringWriter tw = new StringWriter();   
HtmlTextWriter hw = new HtmlTextWriter(tw);   
ctrl.RenderControl(hw);   
String sb = tw.ToString();   
Response.Write(sb);   
Response.End(); 
}

protected void Button2_Click(object sender, EventArgs e)
{   
TabPanel tbPnl = TabContainer1.ActiveTab;   
RenderControl(tbPnl);
}

But I got the bellow mentioned exception when I click on the button in the application.

Script control 'TabPanel2' is not a registered script control. Script controls must be registered using RegisterScriptControl() before calling RegisterScriptDescriptors().
Parameter name: scriptControl

Any Help regarding this will be greatly appreciated..

Thanks in Advance...

Re: HTML Print of Selected Tab

Peace ON21-Jul-10 21:30

Global Distribution System in ASP.NET website

21-Jul-10 21:30

From following code you will get particular TabPanel. So you
need to check properties of tab panel to get HTML.
Then you can print easily.

AjaxControlToolkit.TabContainer container = (AjaxControlToolkit.TabContainer)TabContainer1;
foreach (object obj in container.Controls)
{
    if (obj is AjaxControlToolkit.TabPanel)
    {
        AjaxControlToolkit.TabPanel tabPanel = (AjaxControlToolkit.TabPanel)obj;
        //Now check properties of tabPanel to get HTML.
        //there must be some way.
    }
}

HTH

Jinal Desai - LIVE
Experience is mother of sage....

Ahamed Azeem21-Jul-10 20:55

Ahamed Azeem

21-Jul-10 20:55

Dear Gentlemen,

I want to connect to GDS(Global Distribution System) for hotel booking in my website.. how can i go for it.. could you pls let me know about it. I tried in google but unfortunately i couldnt get proper resources.

please provide some links about this

Ahamed Azeem
Technical Lead

Re: Global Distribution System in ASP.NET website

Peace ON21-Jul-10 21:15

Re: Gridview Column colors

21-Jul-10 21:15

Find following link useful for the same.

GDS Integration[^]

HTH

Jinal Desai - LIVE
Experience is mother of sage....

Gridview Column colors

codingrocks21-Jul-10 18:40

codingrocks

21-Jul-10 18:40

I have a gridview control in aspx page. Suppose I have 3 columns, I need to have different colors for each column. I want to set different colors for three different columns in the gridview. Is it possible to set the colors in aspx page.

I have tried implementing, but could find any solution.

Please suggest me a way to achieve this...

CodingRocks

ASP.NET,C#.NET Programmer
BANGALORE

"Winners don't do different things. They do things differently. ...

Prosanta Kundu online21-Jul-10 19:01

Prosanta Kundu online

21-Jul-10 19:01

Set ItemStyle-BackColor property of BoundField

XML

<asp:BoundField ItemStyle-BackColor="Yellow" ....

Re: Gridview Column colors

Peace ON21-Jul-10 19:44

Getting sessions to ASMX webservice

21-Jul-10 19:44

You can also change color of particular row or column at
run time based on some condition.
i.e.

if(SomeCondition)
{
    datagridview1.Columns[0].DefaultCellStyle.BackColor = Color.Aqua
    datagridview1.rows[3].DefaultCellStyle.BackColor = Color.Aqua
}
else
{
    datagridview1.Columns[0].DefaultCellStyle.BackColor = Color.Blue
    datagridview1.rows[3].DefaultCellStyle.BackColor = Color.Blue
}

HTH

Jinal Desai - LIVE
Experience is mother of sage....

Matt Cavanagh21-Jul-10 8:40

Matt Cavanagh

21-Jul-10 8:40

I have an ASMX webservice hosted alongside my ASP.NET web app. It is in the same project, hosted as the same IIS web application, and compiles to the same DLL. Now, I need to get the users session into the Webservice. To test this I made this simple method:

[WebMethod(EnableSession = true)]
    public string checkSession()
    {
        return HttpContext.Current.Session["userid"].ToString();
    }

So, first I login to my web app, then in the browser goto my webservice and click "checkSession" on that auto generated test page. I have tested this on 3 computers. All 3 of those work fine with the webapp(so the sessions are being created etc), and 2 of those return the value of Session["userid"] on invoking the webmethod, however the last computer returns "Object reference not set to an instance of an object" because Session is null.

So, whats the difference between these computers and why can my ASP.NET app get the sessions on all computers but the webservice cant?
I have also tested with my cellphone and it works there too.

Thanks Smile | :)

Strive to be humble enough to take advice, and confident enough to do something about it.

Re: Getting sessions to ASMX webservice

Yusuf21-Jul-10 9:01

Re: Getting sessions to ASMX webservice [modified]

21-Jul-10 9:01

Well, See this msdn[^] article about sharing your session state between asp.net and web services.

Yusuf
May I help you?

Matt Cavanagh21-Jul-10 9:30

Matt Cavanagh

21-Jul-10 9:30

I have looked through that article, and have done everything up to the point about cookie containers.
My webservice proxy has no such object, what am I missing?
EDIT:
Ok so I found that theres and attribute in the config file to enable the cookie container. But now my silverlight(which is what I am using to connect to the webservice) now gives this error:
"CookieContainer is not supported when using a browser-based HTTP stack. Cookies will be automatically managed by the browser. To gain manual control over cookies, switch to a different HTTP stack, for example by using WebRequest.RegisterPrefix with WebRequestCreator.ClientHttp."

But I don't think this has to do with Silverlight at all, or the cookiecontainer, because even that auto generated test page for the ASMX doesn't work.

Strive to be humble enough to take advice, and confident enough to do something about it.

modified on Wednesday, July 21, 2010 4:45 PM

problem writing in doc file

Dhyanga21-Jul-10 5:39

Dhyanga

21-Jul-10 5:39

Hi,

I am having problem in displaying report in doc file. the code is

SqlConnection cnx = new SqlConnection(categories.strCnx);
cnx.Open();
string query = @"select * from categories";
SqlCommand cmd = cnx.CreateCommand();
cmd.CommandText = query;
SqlDataReader dr;
HttpContext.Current.Response.Clear(); //clear anything in io buffer
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=categories.doc");
HttpContext.Current.Response.Charset = "";
HttpContext.Current.Response.ContentType = "application/vnd.ms-document";
HttpContext.Current.Response.Write("categories" + '\n');

try
{
i = 0;
dr = cmd.ExecuteReader();
while (dr.Read())
{
s[i]= dr[0].tostring();
i++;

}
for (int j = 0; j
{
HttpContext.Current.Response.Write(s[j].ToString() + '\n');
}

HttpContext.Current.Response.End();
}
catch(Exception ex)
{
string pt = ex.ToString();

}

In this code, if I write the file inside the while(dr.read()), it works fine but when i tried to write it inside the for loop, it doesn't give the output.

Why is that and how to solve it ?? Any idea ??

Re: problem writing in doc file

Yusuf21-Jul-10 6:06

Re: problem writing in doc file [modified]

21-Jul-10 6:06

SayamiSuchi wrote:
it doesn't give the output.

What does that mean? Did you debug it? What did you see/get? Give us your error message so we can understand it better.

Yusuf
May I help you?

Dhyanga21-Jul-10 6:14

Dhyanga

21-Jul-10 6:14

yes i did debug.
it said

System.Threading.ThreadAbortException: Thread was being aborted.
at System.Threading.Thread.AbortInternal()
at System.Threading.Thread.Abort(Object stateInfo)
at System.Web.HttpResponse.End()
at categories.Default_View.filetesting() in C:\Documents and Settings\smanandhar\My Documents\Visual Studio 2008\Projects\categories\Default_View.ascx.cs:line 1209

suchita

modified on Thursday, July 22, 2010 10:29 AM

Java script reset problem

immu521-Jul-10 5:37

immu5

21-Jul-10 5:37

I have one asp.net page (Page1) with llots of controls.
After submitting this page, I have another page (Page2) on which there is one link which redirects me again to the same page from which I came from but with prefilled values. On the original page (Page1), there is one link "Clear Fields". Onclick of this link I want to clear all the controls.
document.forms[0].reset() --- Not working in this case.

Before submitting the form, if I fill up the values and click on "Clear Fields" link, I am able to reset all the controls but once I submit the form and came back to the same page, the above javascript code is not working.

Can anyone help me!!

Yusuf21-Jul-10 6:18

21-Jul-10 6:18

Well, you would need to set all the control values to their default values. Look Here[^]

Yusuf
May I help you?

Not Active21-Jul-10 8:53

Not Active

21-Jul-10 8:53

First of all it seems an extremely poor design to one a page that simply redirects back to the page you came from, and is most likely causing you more difficulties. Using viewstate, or some other form of persistence, the controls can retain there values between postbacks. You should also be using a cross-browser JavaScript library such as JQuery.

I know the language. I've read a book. - _Madmatt

immu521-Jul-10 8:59

immu5

21-Jul-10 8:59

Here is my problem...

On first page, i have some fields for user input. Based on user input on first page, will display the results on second page.
On second page, i have modify button, which takes me to first page. So clicking on reset button on first page doesn't clear off all the fields if i coming from second page.

Before submitting the first page, the values are resetting.