Figure there is a simple solution to this problem but I have been unable to find it.I have databinding in an ASP.Net application to a GridView. This gridview is bound to an ObjectDataSource as per standard usage.The problem I have is that one of my bound fields uses the property DataFormatString="{0:C}" and due to the currency format being displayed when an update is attempted and the object recreated I get a error as such "$13.00 is not a valid value for Decimal."Clearly this is a result of the column using a FormatString and then attempting to bind it back to a decimal property I have in my object called UnitPrice.I am assuming there is some markup I can set that can specify how the value is translated back?For anyone curious the solution ended up looking like this...
Quick question here. I'm sure it's possilbe, just can't get it to work.
I've got a gridview. In have a gridview. The gridview is bound to a list of my custom class. The class exposes a link to an image as well as the image's height and width. I have a Image Control in the gridview. I've bound the Image Url to the correct property. Now, I'd like to bind the height and width properties as well. But everytime I do that I get the following error:
Cannot create an object of type 'System.Web.UI.WebControls.Unit' from its string representation '"<%#Bind("GetImageHeight()")%' for the 'Height' property.
Again, I am new to the ASP.NET world, and I come from a Windows Forms background. I'm working with an ObjectDataSource that retrieves a collection of business objects. With the collection, I am going to be binding it to a CheckBoxList and other various controls. The business object that I am using is an Employee.
To get all of the employees, I create an ObjectDataSource and set the "Select" method. I then set the DataSourceID of the CheckBoxList to be that of the ObjectDataSource. When I load the page for the first time, I see all of the employees. Now, the user goes through this page and selects all the employees they want to see information about (by checking the box next to the employee name). Finally, the user hits the button called "Display." Upon postback how do I get a list of those employees? I've tried the following solution, but I'm not sure if it's the best practice in obtaining all those employees again. Here's my solution...
In the CheckBoxList, I set the DataTextField to the Employee's name. I also set the CheckBoxList's DataValueField. This property is a little different. I set this to be a UNIQUE IDENTIFIER, which can distinguish this employee from other employees. Now, when the user hits the button "Display" I use my ObjectDataSource again and MANUALLY call ObjectDataSource.Select(). I cast the returned value as a List<Employee>. Finally, I iterate through all list items in the CheckBoxList...
[Code]....
If the item is selected, I parse through my list of employees that was returned from the bjectDataSource.Select(). I use the item.Value and compare it to each employee's "key." If the key is found, I know that the employee is selected. I put this employee in another list called EmployeesSelected.
Finally, I take EmployeesSelected (which is a List) and set my GridView's .DataSource and call .DataBind() on the GridView.
Is this the "best practice" of re-obtaining the Employees that are selected on my page, or am I making this too complicated?
What is the format for databinding to a complex "object"? I have a linq to sql class that has containment, i.e object.containedobject.I want to reference the sub objects fields declarative.So I've tried my MySubField.MyBasicProperty and that did not work, as well as, MySubField_MyBasicProperty.
im trying to use dynamic object in a databinding tag , it gives me error that the property does not exists even though i can see all the properties there in the vs debug mode
here is what im trying to do:
C#:
my method signature:
public static dynamic MyMethod()
ASPX:
in control itemtemplate:
<%# MyMethod().SomeProperty %>
if also trite the other way:
C#:
public static object MyMethod()
ASPX:
<%# ((dymanic)MyMethod() ).SomeProperty%>
But i dont know why it cant resolve the properties , even though i can see them when the databinder control throws an exception (its working fine outside the databinder tag (ie normal aspx tags <% %>)
I have a user control with a datalist. I just want to do some simple binding but keep getting an object reference not set to an instance of an object error. The following is the code, I am sure I am just missing something simple:
Dim dc As Forms.DataClassesDataContext = New Forms.DataClassesDataContext Dim formQuery = From fq In dc.v_form_questions _ Where fq.FormTypeID = FormTypeID _
[code]...
When I debug, I see values for the formQuery; I am also able to loop through the formQuery and response.write a field out, however every time I try to bind it to a databound control, I get the Object reference not set to an instance of an object error.I initally was using a simple LinqDataSource object, but needed to set the where parameter to the FormTypeID property of this usercontrol. I had a Where condition defined on Page Init, but started getting the object reference error.
I am using an ObjectDataSource control to call a MapInfo object. This object has two properties:
public IList Visits public int TotalAvailable
The select method returns an IList but the TotalAvailable property is also populated. I have set the TypeName in the ObjectDataSource to the MapInfo object but because the Select method only returns the IList I don't have access to the TotalAvailable.
[code]....
Is there any way to access this value. I know it is being populated in the MapInfo object but all that gets returned from the Select method is the IList
When I get an Object Ref error, it can sometimes be a real pain to find out which variable is causing the error (when you can't debug). Is there a way for this error to throw the classname that isn't assigned?
For every row in my 'table' I am manually creating, there must be a LinkButton to delete a database row that matches a column in the table. Because no 2 controls can have the same name, I've had to use a GUID to name them so they're all unique.
Problem is, right now when I click Delete, the page posts back with no changes, but I've been told that I need to recreate the controls - but how do I recreate them in Page_Load when their ID's are randomly generated? Here's my code:
I'm trying to create a dynamic table (inside a gridview) with some objects. The initial creation is fine, and I store all the selectedindexes in viewstate to recreate it upon postback. This, seemingly, works fine as well, but...After the postback, when I get into the selectindexchanged even handler, I can see the new selectedindex, but the original control sending it is reset to it's initial value (because I reset them upon postback).Anyone know a fance way of doing this?Here's my code:
DataBinding: 'System.Data.DataRowView' does not contain a property with the name 'p2_area_name'.
Description: An unhandled exception occurred during the execution of the current web request. review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Web.HttpException: DataBinding: 'System.Data.DataRowView' does not contain a property with the name 'p2_area_name'.
Also, I need tp populate data from database in the Area dropdown but not able to do so..
i have an Gridview with BoundFiled, for the bound field headertext alo coming from the table, but i dont know how to bind the headertext and data. i have used below code
I have a dropdownlist (drpClients) bound to an object datasource (odsProgramClients). In the dropdown's databound event, I load a dynamic table based on the selected item in the dropdownlist. This all works well. However, if I force a problem in odsProgramClients select method, it continues to the databound event of the dropdown and attempts to load the table, even though dropdownlists underlying select method failed. I wish to stop the databound event from firing if there is a problem in the select method. I have code that traps the error in odsProgramClients select method.
[Code]....
[Code]....
How do I stop the dropdownlist from databinding, if there is an error in it's underlying datasource?
i have a FormView, it renders fields from a SQLServer database but also much static text specific to the database value I get. I dont know if this can be done in the code behind and put all this in a function . I put it in my formview
<ItemTemplate> <% If Eval("Feature1") = "Yes" Then %> <%# Eval("Username") %> A lot of text <% elseIf Eval("Feature1") = "No" Then %> <%# Eval("Username") %>
A lot of different text
<% End If %> </ItemTemplate>
If I do the code above I get error message:
Databinding methods such as Eval(), XPath(), and Bind() can only be used in the context of a databound control. Can this be done within the formview?
In the VS2005 environment, when I test my session to make sure the page redirects to the main page (itself) if the session is null, it works. There is no error.
The function I use for this is:
[code]....
However, when it is in the production environment in IIS 6.0, when the session has timed out, and I then do a postback by doing some slider control, I see the page reload but immediately thereafter, it throws a Server Error exception of : Object reference not set to an instance of object.
however, why is it that the Slider1_TextChanged event fired even even after during page_load, the page was told to do a response.direct ?? shouldn't the entire page have gone through a full-page refresh life cycle ? why did it continue on to attempt to raise the Slider1_TextChanged event?
I'm new to programming in ASP.NET, but I'm making my way through Wrox's Beginning ASP.NET 3.5 in C# and VB.NET.
I'm at a section where I'm creating a BasePage. I successfully created a BasePage by creating a new class file in my App_Code folder called BasePage.cs with the following code:
[Code]....
If I run that code everything works out fine. The page loads and all is well. But, if I try to do the same thing to a page that uses my MasterPage.master file, I get the following error:
Object reference not set to an instance of an object.
Description:
An unhandled exception occurred during the execution of the current web request. review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Why is that? In the example code from the book (that also uses a MasterPage.master file), everything excutes and runs just fine. But in my test, I get the above error. I've tried comparing my pages to the books included source pages, but I can't find any differences.
We have an applicaiton that was converted to the new framework using the wizard in Visual Studio 2008. When we install the applicaiton in production and change the iis settings to use the 2.0 framework we start to see these errors in the event viewer on the web servers. We are using SQL Server Session State and have 3 web servers in a load balancer. Object reference not set to an instance of an object.</Message><StackTrace> at System.Web.SessionState.SessionStateModule.PollLockedSessionCallback...
I have just recently converted my VB code to C# and now having this error when I try to add an item to my listbox, and the value is coming from the item page. I get the error at this segement:
lstboxCart.Items.Add(cartItem.Display());
My listbox is supposed to add the product's name, quantity, and price onto one row.
Here's what I have so far:
[code]...
[Code]....
[Code]....
My guess is that the source of the problem could be in the foreach loop from my cart class, shouldn't I be using that for arrays only? If I need to post any markup code or any other class, let me know.
I have the following code in my form load that loads the reports and assigns it to crystalreportviewer control. If Not IsPostBack Then
[Code]....
Following is the ApplyCRLogin Class
[Code]....
Now when I run the site it prompts me for the parameters and when I enter them and click on OK, I get the following error. "Object reference not set to an instance of an object." But the strange thing is if I comment the "If Not IsPostBack Then" condition, my report works fine. The problem is even when I want to go to the next page in report, the code get executed again and this takes time. Is there any other way to fix this?
I am trying to run the 15 minutes movies MVC application but I got the following error:
Object reference not set to an instance of an object.
Description:
An unhandled exception occurred during the execution of the current web request. review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
