How can I solve "Object Referance not set to an instance of an object" error problem? - ASP.NET Discussion Boards

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Re: 2 data text field columns in listbox

Deepak the Cool6-Oct-08 2:51

Deepak the Cool

6-Oct-08 2:51

Do that CONCAT your column fields in Your Query.and get return back it
then bind your List.

Like this

select (id +' | ' +name )as name,id from Emp

and bind your
List.DataTextField="name";
List.DataValueField="id";
..............
..............

Deepak

Smile a Lots,Its Costs Nothing

adding to single datattable which is in a class from user control referenced in different part of same page

justintimberlake6-Oct-08 1:22

justintimberlake

6-Oct-08 1:22

I have a user control which is used in three different place of page. i have to save the data from each of these user control
to first datatable(temporary) and then finally from that datatable to database.

so if i have a usercontol1 which have textboxes and submit button (temp_submit) these user control is used in different place of same page
so when i press temp_submit from one place i.e where usercontrol is used, it should save to datatabe now again if the same user control
from another place in page, if button (temp_submit) is clicked the then the values of text box should be append to that datatable
and latter on when i click main submit button every thing should be save to datatbase.

Re: adding to single datattable which is in a class from user control referenced in different part of same page

Sandeep Akhare6-Oct-08 1:59

Sandeep Akhare

6-Oct-08 1:59

Just create a property that will differetiate between the control's submit button will update database and the control's submit button will update DataTable
Assign this property in while decalring the cotrol only
<UC:UCNAME id="IDPARYT" UpdateDatabase="true" runat="server"></UC:UCNAME >

lt;UC:UCNAME id="DontUpdate" UpdateDatabase="False" runat="server"></UC:UCNAME >

In code Behind in button click just check this property
if(UpdateDatabase)
{
Update Database
}
else
{
Update Data Table
}

If things are very comlicated then create different user control instead
it is not going to hit perforamance any way

Thanks and Regards
Sandeep

If If you look at what you do not have in life, you don't have anything,
If you look at what you have in life, you have everything... "

Check My Blog

want invisiable window open thorugh javascript.

UD(IA)6-Oct-08 0:54

UD(IA)

6-Oct-08 0:54

hi
is it possible that i open a invisible window open through javascript. is there any attribute of the java function window.open property invisible?
Big Grin | :-D

I will do my best?
Integrated Solutions, Bikaner (Raj.), India

Re: want invisiable window open thorugh javascript.

Sandeep Akhare6-Oct-08 1:00

Sandeep Akhare

6-Oct-08 1:00

I think for that you will have to write invisible javascript code Laugh | :laugh:

just kidding
Not possible i think
Can you tell why you want to open such window ?
Whats the requirement

Thanks and Regards
Sandeep

If If you look at what you do not have in life, you don't have anything,
If you look at what you have in life, you have everything... "

Check My Blog

Re: want invisiable window open thorugh javascript.

Abhijit Jana6-Oct-08 1:14

Abhijit Jana

6-Oct-08 1:14

You can do one think, just set height and width of window to 1 ,1 and set left and top to 4000 or such a value that will come in resoulation.
hope this will helps you Smile | :)

cheers,
Abhijit
Think Sharp | Code Sharp | C Sharp

Re: want invisiable window open thorugh javascript.

J4amieC6-Oct-08 2:08

J4amieC

6-Oct-08 2:08

This method will be blocked by every single popup blocker out there....for very good reason. There is no (i repeat: NO) legitimate reason to want to hide a popup from a user.

How can I solve "Object Referance not set to an instance of an object" error problem?

JUNEYT6-Oct-08 0:27

JUNEYT

6-Oct-08 0:27

Hi,

I have been getting the following error message whatever I tried to get rid of it, I couldn't succeed it. How can solve the problem? I tried to define the dropdownbox with (Dim myYearBox as New Dropdownlist) and it didn't work out too.

Error message is :"Object Referance not set to an instance of an object"

<br />
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load<br />
<br />
<br />
        If Page.IsPostBack = False Then<br />
<br />
<br />
            Dim myYearBox As DropDownList = CType(FormView1.FindControl("GetYear"), DropDownList) '<< ERROR<br />
<br />
            myYearBox.Items.Insert(0, Now.Year.ToString)<br />
            myYearBox.Items.Insert(1, (Now.Year + 1).ToString)<br />
<br />
<br />
            'GetYear.Items.Insert(0, Now.Year.ToString)<br />
            'GetYear.Items.Insert(1, (Now.Year + 1).ToString)<br />
<br />
            Call populateDayFromBox(Now.Year, Now.Month)<br />
<br />
        End If<br />
<br />
    End Sub<br />
<br />

What a curious mind needs to discover knowledge is noting else than a pin-hole.

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

eyeseetee6-Oct-08 0:54

eyeseetee

6-Oct-08 0:54

Make sure GetYear is spelt correct and is in the formview
How do you know which line is object reference?

Deliver yesterday, code today, think tomorrow.
"http://www.heuse.com/cphumor.htm"

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

JUNEYT6-Oct-08 1:10

JUNEYT

6-Oct-08 1:10

It is spelled correctly and it is inside the formview. The error line was pointing the line where the line marked '<< Error'

Thanks.

What a curious mind needs to discover knowledge is noting else than a pin-hole.

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

Jaffer Mumtaz6-Oct-08 2:33

Jaffer Mumtaz

6-Oct-08 2:33

Hi,

Try to check FormView1.FindControl("GetYear") is returning null. To my experience FindControl in Asp.Net sometimes returns null even if the control is there. I think this is why you are getting this problem. Put a check on the code if its null then do something else.

Regards

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

JUNEYT6-Oct-08 4:47

JUNEYT

6-Oct-08 4:47

Hi Jaffer,

The problem is dropdownboxes are not bind to any dataobjects. I was aimed to populate these boxes in runtime. However if I bind them to an objectdatasource, I am not able to define an event eg. (Dropdownbox_Clicked) because they are inside of th Formview control.

Therefore, I decided not to bind them and I don't use formview now. However now I am facing to another issue, How I am giong to assign their values as inputparameter to objectdatasource insert event below.

Here is the code sample. All I need to pass 5 doprdownboxes selectedvalue arguments to below procedure as inputparameters. When I click a button, these paramaters must be carried to following procedure.

<br />
    Private Sub ObjectDataSource1_Inserting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ObjectDataSourceMethodEventArgs) Handles ObjectDataSource1.Inserting<br />
<br />
        Dim ParamsFromPage As IDictionary = e.InputParameters<br />
<br />
        Dim NewObj As New property_availability(0, 0, 0, 0, "")<br />
<br />
        NewObj.Getyear = Int32.Parse(ParamsFromPage("GetYear")).ToString<br />
        NewObj.GetMonth = Int32.Parse(ParamsFromPage("GetMonth")).ToString<br />
        NewObj.GetDayFrom = Int32.Parse(ParamsFromPage("GetDayFrom")).ToString<br />
        NewObj.GetDayTo = Int32.Parse(ParamsFromPage("GetDayTo")).ToString<br />
        NewObj.GetStatus = ParamsFromPage("GetStatus").ToString<br />
<br />
        ParamsFromPage.Clear()<br />
<br />
        ParamsFromPage.Add("GetYear", NewObj.Getyear)<br />
        ParamsFromPage.Add("GetMonth", NewObj.GetMonth)<br />
        ParamsFromPage.Add("GetDayFrom", NewObj.GetDayFrom)<br />
        ParamsFromPage.Add("GetDayTo", NewObj.GetDayTo)<br />
        ParamsFromPage.Add("GetStatus", NewObj.GetStatus)<br />
<br />
    End Sub<br />
<br />

What a curious mind needs to discover knowledge is noting else than a pin-hole.

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

AlexeiXX36-Oct-08 5:03

AlexeiXX3

6-Oct-08 5:03

Instead of using the object datasource to insert, why dont you call your busines object's insert method directly??

Alexei Rodriguez

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

JUNEYT6-Oct-08 5:28

JUNEYT

6-Oct-08 5:28

I use Business object's insert method actually. Please see the code below. However I decided not use Formview because in runtime I must control dropdownboxes and their events. Now I am not able to pass the values of these boxes to below procedure because this boxes are not bind to objectdatasource anymore. I have to externally bind them somehow but I don't knwo how to do that.

<br />
    Private Sub ObjectDataSource1_Inserting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ObjectDataSourceMethodEventArgs) Handles ObjectDataSource1.Inserting<br />
<br />
        Dim ParamsFromPage As IDictionary = e.InputParameters<br />
<br />
        Dim NewObj As New property_availability(0, 0, 0, 0, "")<br />
<br />
        NewObj.Getyear = Int32.Parse(ParamsFromPage("GetYear")).ToString<br />
        NewObj.GetMonth = Int32.Parse(ParamsFromPage("GetMonth")).ToString<br />
        NewObj.GetDayFrom = Int32.Parse(ParamsFromPage("GetDayFrom")).ToString<br />
        NewObj.GetDayTo = Int32.Parse(ParamsFromPage("GetDayTo")).ToString<br />
        NewObj.GetStatus = ParamsFromPage("GetStatus").ToString<br />
<br />
        ParamsFromPage.Clear()<br />
<br />
        ParamsFromPage.Add("GetYear", NewObj.Getyear)<br />
        ParamsFromPage.Add("GetMonth", NewObj.GetMonth)<br />
        ParamsFromPage.Add("GetDayFrom", NewObj.GetDayFrom)<br />
        ParamsFromPage.Add("GetDayTo", NewObj.GetDayTo)<br />
        ParamsFromPage.Add("GetStatus", NewObj.GetStatus)<br />
<br />
    End Sub<br />
<br />
<br />

What a curious mind needs to discover knowledge is noting else than a pin-hole.

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

AlexeiXX36-Oct-08 8:50

AlexeiXX3

6-Oct-08 8:50

Unless im missing something, i dont see any sense on this previous code

You read the values from e.insertparameters into ParamsFromPage
Yo add ParamsFromPage into a temp object
You clear ParamsFromPage
You add them back to ParamsFromPage

???
What are you doing?

Alexei Rodriguez

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

JUNEYT6-Oct-08 9:05

JUNEYT

6-Oct-08 9:05

Actually I have paased this paramaters to a class object if you carefully examine the code and then I pass the paramaters to insert function of objectdatasource object. In back and there is a kist object what keep the all the values.

Thanks Alex.

What a curious mind needs to discover knowledge is noting else than a pin-hole.

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

AlexeiXX36-Oct-08 9:15

AlexeiXX3

6-Oct-08 9:15

NewObj.Getyear = Int32.Parse(ParamsFromPage("GetYear")).ToString
NewObj.GetMonth = Int32.Parse(ParamsFromPage("GetMonth")).ToString
NewObj.GetDayFrom = Int32.Parse(ParamsFromPage("GetDayFrom")).ToString
NewObj.GetDayTo = Int32.Parse(ParamsFromPage("GetDayTo")).ToString
NewObj.GetStatus = ParamsFromPage("GetStatus").ToString

ParamsFromPage.Clear()

ParamsFromPage.Add("GetYear", NewObj.Getyear)
ParamsFromPage.Add("GetMonth", NewObj.GetMonth)
ParamsFromPage.Add("GetDayFrom", NewObj.GetDayFrom)
ParamsFromPage.Add("GetDayTo", NewObj.GetDayTo)
ParamsFromPage.Add("GetStatus", NewObj.GetStatus)

What are you doing here??
paramsFromPage has the same values that i had in the beggining

By the way...
If carefully look at this:
NewObj.GetDayTo = Int32.Parse(ParamsFromPage("GetDayTo")).ToString
I think that getDayTo expects an int32, you are making extra conversions, you case the value to int32 and then to string with the tostring method and then the result is casted back to int32 when you assign it

Alexei Rodriguez

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

JUNEYT6-Oct-08 11:15

JUNEYT

6-Oct-08 11:15

You are right Alex. I forgot to take it out actually. Thanks Smile | :)

What a curious mind needs to discover knowledge is noting else than a pin-hole.

Re: How can I solve "Object Referance not set to an instance of an object" error problem?

ToddHileHoffer6-Oct-08 3:01

ToddHileHoffer

6-Oct-08 3:01

Well, if you are 100% sure the name is correct (including the case) try executing the code at a later stage in the page's life cycle. Perhaps the control will not be null in page_preRender event.

I didn't get any requirements for the signature

Does .Net Framwork needed?

Pedram Behroozi6-Oct-08 0:13

Pedram Behroozi

6-Oct-08 0:13

Hello,
I'm newbie in ASP.NET and I want to develop a website using it but does my visitors need to install .Net Framework to visit my website? Confused | :confused: