I'm getting an "Object Reference Not Set to an Instance Of An Object Error" in a Web User Control that I've created when referencing any control in the Code Behind. Intellisense reports that the control exists in the aspx, but whenever I build and run I get that error.
[Code]....
Initially, the error occurs on this line...
[Code]....
Here is the contents of my test.ascx file:
<%@ Control Language="C#" AutoEventWireup="true" CodeFile="test.ascx.cs" Inherits="UserControls_test" %>
<p id="XXX">aaa</p>
and here is the contents of my test.ascx.cs file:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class UserControls_test : System.Web.UI.UserControl
{
protected void Page_Load(object sender, EventArgs e)
{
this.XXX.InnerHtml = "BBB";
}
}
I get an error when I refer to the id, "XXX" (underlined above) in code behind which reads: 'UserControls_test' does not contain a definition for 'XXX' and no extension method 'XXX' accepting a first argument of type 'UserControls_test' could be found (are you missing a using directive or an assembly reference?)
I have tried XXX.InnerHtml and I have tried this.XXX.InnerHtml and get same problem.
How do I successfully refer to ID'ed HTML elements in code behind?
I am attempting to access a textbox control on a master page from a code behind base class but having problems.
I have 3 levels of master pages. m1.master is the master page for m2.master which is the master page for m3.master.
m3.master has a textbox as shown below
<%Master
Language="C#"
MasterPageFile="~/m2.master"
AutoEventWireup="true"
CodeFile="M3.master.cs"
Inherits="M3"
%>
<asp:Content
ID="Content5"
ContentPlaceHolderID="M2"
Runat="Server">
<asp:TextBox
ID="text1"
runat="server"
></asp:TextBox>
<asp:ContentPlaceHolder
ID="M3"
runat="Server"></asp:ContentPlaceHolder>
</asp:Content>
I have a content page c1.aspx that uses m3.master as its master page as shown below:
<%@
Page
Title=""
Language="C#"
MasterPageFile="~/m3.master"
AutoEventWireup="true"
CodeFile="c1.aspx.cs"
Inherits="_c1"
%>
<%@
MasterType
VirtualPath="~/m3.master"
%>
<asp:Content
ID="Content1"
ContentPlaceHolderID="M3"
Runat="Server">
</asp:Content>
My content page codebehind class inherits from a base class BaseForm
public partial
class
_c :
BaseForm{}
The problem that i am having is that I cannot access the texbox from the class BaseForm. The BaseForm code is as follows:
using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public...........
I'm getting a null reference exception for txt1
I have the following Report class that I want to serve as the base class for my pages.
I will have several aspx files MyReport1.aspx, MyReport2.aspx, ... MyReportN.aspx
---------
Report.cs
---------
public class Report : Page
{
protected readonly ListView reportListView; [code]....
I am working on converting a project from C# to VB and am facing this weird issue. 1 page cannot compile and I get the reference error, but the weird thing is that the compiler shows the error as coming from ASP.NET generated code. Visual Studio shows me that error is coming from my ASPX page. I cannot seem to figure out why or where this error is occuring. Also if I take the inherits attribute out I don't get the compilation error. The code in aspx page is below:
[Code]....
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View 1 RepliesI have an activex OWC11 Chartspace on my form. I wish to be able to access this object in my code behind page instead of scripting the code in the asp page. Has anyone any idea how to get a handle to the activex chartspace object from the code behind. I know how to create an OCW chart and then display it as a jpeg from the code behind page but the activex chart component offers more use with the chart opbect on the page rather than a jpeg?
<
object
id=ChartSpace1
[code]...
How do you made a reference to an imagebutton in the code behind? I'm trying to show a high priority "!" image if an "h" was in the label. the code below.
[Code]....
I have a class that derives from System.Web.UI.Page and have set my pages to derive from this custom page class instead of Page. At runtime, the controls are never initialized and throw a NullReferenceException. I've changed some class names and namespaces in the pasted code to protect the innocent. The only thing that I currently override in my PageBase is OnPreLoad and I do call the base.OnPreLoad. I'll eventually add more functionality to this PageBase but for now all that it has is this:
[Code]....
I've tried putting this into a class library (with System.Web referenced) and I've also tried moving the class into the web application and had the same results either way. As another strange twist, I have another class with derives from PageBase called IndexPageBase and it doesn't have this problem:
[Code]....
[Code]....
[Code]....
I lifted some nice code to handle memberships, but I want to add a customer specific field. My issue is how to reference my class from the inline c# code.
[Code]....
The problem is the line csUserProperties.AddNew(intUserId, lngCustomerId); -- I get the error "The name 'csUserProperties' does not exist in the current context. I have <%@ Import Namespace="csUserProperties" %> at the top of the file. I also tried everything with no namespace in the class below.
Is it possible to add javascript reference dynamically from code behind aspx.cs?Like this:
private void AddScriptReference(string path)
{
//Add reference to <head></head>
}
[code]...
I have a <div> element in a web page. I've assigned it an "ID" and made it a server-side control by using "runat=server". How do I define that <div> in the code-behind. I'm been looking at the "System.Web.UI.HtmlControls" namespace and not sure what to use. The reason I need to do this is because within this <div> is a "Submit" button which will cause a postback. When I click the submit button the first thing it does is it executes a procedure to perform edit checks on the various textbox controls. If a control is empty, a message pops up. When the user clicks "Ok" for the message, the <div> disappears because when the form loads, the <div> style.display property is set to "none" by default. Basically, all I want is for the <div> not to disappear when the edit checks are performed and a messagebox pops up.
View 7 Replieshow user controls can communicate with each other within an asp.net application. I am facing many obstacles at the moment regarding this problem. For example, is it possible to set the visible property of a panel on one user control based on what happens in another?
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I need reference a Treeview from a shared sub so I can run a databind on it after the the sub has finished doing it's thing.
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saying "Object reference is not set an instance".
how to refresh data from another user control ...
My senerio below :
1 Aspx page
2. User control
calling usercontrol databinding method from aspx page but once it get refreshed ,not allowed to bind it again..
When we reference a DLL. It creates that DLL in the BIN folder of our project.My question is although the BIN folders are not included in the web application project thenhow come all the code works? When I right click on the Bin folder I get an option "Include in Project"So how come I am able to use all the methods inside the dll's in the BIN folder even though the BIN folder itself is not included in the Project? Do we ever include the BIN folders?
View 10 RepliesI'm trying to use a ModalPopupExtender in a user control, so the TargetControl is on the previous (parent) page. In the PageLoad event of the user control, the following code finds the MPE and the button from the previous page, but I don't understand how to actually assign the button to the MPE as the TargetControlID.
[Code]....
Thing is, when my service is providing result of type string my client .aspx page is working fine and it gives reference in my code. But now I changed my service to provide custom data type and I can't see service reference in my code, intellisense doesn't offer it at all. What am I missing here? WCFTestClient.exe is giving good results but I can't create my own in VS 2008
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Ex.
<asp:TextBox Width="245px" ID="txtName" runat="server"></asp:TextBox>
VB file: txtName.text = "Some text"
txtName dosent show up by intellisense.
i am trying to enter a value into a texbox that is placed inside a user control called CollectionRequest. i have referenced this user control in my code behind and created an instance of it but i seem to get the above error when i try to enter some manual text. code as follows:
protected CollectionRequest collReq;
protected void Page_Load( object sender, EventArgs e )
{
collReq = (CollectionRequest)LoadControl("~/CollectionRequest.ascx");
TextBox _txt_address = (TextBox)collReq.FindControl("txt_Address");
_txt_address.Text = "thisi is an address";
control has been referenced in source file
<%@ Reference Control="~/CollectionRequest.ascx"%>
i am caling this code in my Approval.ascx.cs code. both the user controls are displayed together in the default.aspx page one above the other.
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The type 'Microsoft.Practices.EnterpriseLibrary.Data.Sql.SqlDatabase' is defined in an assembly that is not referenced. You must add a reference to assembly 'Microsoft.Practices.EnterpriseLibrary.Data, Version=3.1.0.0, Culture=neutral, PublicKeyToken=null'.
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string cookieName = Request.QueryString["CookieName"].ToString();
MSDN documentation says that the ScriptManager class is part of the System.Web.UI namespace and I see that I can create a ScriptManager object programmatically. However, I don't see the ScriptManager control on the front-end. Do I need to reference the Ajax Control Toolkit dll in order to have access to control?
View 6 Replies