Forms Data Controls :: How To Catch Object No Set In Asp Tag
Feb 22, 2011i am binding onject in fromview from other webserivice gatewayhow to i catch if the object is not set?
<%# (gw.gatewayobject)gw.gwObject %>
i am binding onject in fromview from other webserivice gatewayhow to i catch if the object is not set?
<%# (gw.gatewayobject)gw.gwObject %>
Here is the code copied from [URL] In asp.net code behind, I use try-catch try to catch any error but never catch it. In SQL database, if I rename Employees to Employeesx or change column DepartmentID to DepartmentIDx, record will not be deleted (it is right) without any error (it is wrong, suppose catch an error).
CREATE PROCEDURE DeleteDepartment
(
@DepartmentID int
)
AS
BEGIN TRANSACTION
DELETE FROM Employees
WHERE DepartmentID = @DepartmentID
IF @@ERROR <> 0
BEGIN
ROLLBACK
RAISERROR ('Error', 16, 1)
RETURN
END
DELETE FROM Departments
WHERE DepartmentID = @DepartmentID
IF @@ERROR <> 0
BEGIN
ROLLBACK
RAISERROR ('Error', 16, 1)
RETURN
END
OMMIT
I have ObjectDataSource and GridView on one of the pages of my asp.net web project.
To initialize ObjectDataSource i use Init event:
protected void ObjectDataSource1_Init(object sender, EventArgs e)
{
ObjectDataSource1.EnablePaging = true;
ObjectDataSource1.TypeName = "CustomerDataSource";
ObjectDataSource1.DataObjectTypeName = "Customer";
ObjectDataSource1.SelectMethod = "GetCustomers";
ObjectDataSource1.UpdateMethod = "Update";
ObjectDataSource1.SelectCountMethod = "GetCustomersCount";
ObjectDataSource1.MaximumRowsParameterName = "maximumRows";
ObjectDataSource1.StartRowIndexParameterName = "startRowIndex";
}
Somewhere in DAL:
public static List<Customer> GetCustomers(int maximumRows, int startRowIndex)
{
try {
... some select to database here...
}
catch (Exception ex)
{
Utils.LogError(ex);
throw ex;
}
}
Now let's imagine that GetCustomers for some reason throws an exception. How could i catch this exception and handle it? I know i can use Application_Error, but i would like to catch this exception somehow on my page and show some friendly message to the user.
I want to catch the session if is null how can I do this. My session is:
Session["kullanici_name"].ToString();
if it is null
Response.Redirect("kulanicigiris.aspx");
And I want to make a logout button. If he /she press the button session=null then page load and check if the session null going to home page.
I am fairly new to the asp.net scene. Having build a dashboard gathering info on my OLAP system's health status, I can't seem to figure out how to make sure that I catch the no connection exception.use the following statements on the datagrid:a) want to change the color of ssas2 button to red if an exception is thrown
View 5 RepliesI have created an ASP page to display records for auditor review and response. The page consists of two repeaters that display 5 rows from a database at a time. for each row displayed, a RadioButtonList, containing two buttons is attached. If the second button is selected, an input text box is displayed to allow auditor comments.
My situation is that I cannot find a way to identify which row is being selected? When I select the Button that should enable the text box, I'm receiving the following error:
"Object reference not set to an instance of an object"
I'm just starting out in ASP coding and would like to know what I'm not doing right?
[code]...
can you please help me to brainstorm the possible causes of this error. I've got a paged repeater with localisation bound programitcally to an sqldatasource using a stored proc. I can post code if needs be but it's rather long. I'm looking for typical causes of this error + will make note for future reference!
erver Error in '/WebSite4' Application.
Object reference not set to an instance of an object.
Description:
An unhandled exception occurred during the execution of the current web request. Please 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.
Source Error:
[Code]....
Line 233:Line 234: Repeater1.DataSource = PagedResultsLine 235: Repeater1.DataBind()Line 236: doPaging()Line 237: End Sub
I am trying to get the value of the id field in my gridview but I keep coming up with this error when i do selectedValue or selecteIndex
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
How do I get that id? What I am trying to do is when the user select that link it will delete that information from the database. Here's my code:
[Code]....
[Code]....
I have a nested gridview
i get error:Object reference not set to an instance of an object
when i try to get the text in the footer template of the inner gridview when clicking on the linkbutton!!!
[code]....
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?
I am using C# and VS 2008 attached with access database, where Date1 is the PKey in Text defined.
I am getting the above error when i am trying to insert it into the access database.
here is my code
aspx :
[Code]....
Code Behind :
[Code]....
My problem is I get an "Object reference not set to an instance of an object." error at runtime on the line "ddl2.SelectedValue = cat1". Ironically I got this from an example on the internet and the only difference is my Cat1 varible which has the correct value at runtime.
<asp:FormView
id="frmCustomer"
DataSourceID="srcCustomer"[code]....
I would like to enable/disable the field BagNo in my gridview, depending on the value of another field in the gridview called ScriptNo, when I click the edit button I get this message "Object reference not set to an instance of an object".
here is the code
Protected Sub GridView1_RowEditing(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewEditEventArgs) Handles GridView1.RowEditing
Dim row As GridViewRow = GridView1.Rows(e.NewEditIndex)
If DirectCast(row.FindControl("ScriptType"), TextBox).Text = "TTA" Then
[Code]....
I tried to get the heade row text with the following code, but it failed.
[Code]....
Error returned was "Object reference not set to an instance of an object." on this line:
[Code]....
The stored proc fired to populate my grid view gets a column CasNo.The GridView has a DataBound item for CaseNo.
[Code]....
Then Why does this get null value: string caseNo = dataRow["CaseNo"] as string;
[Code]....
[Code]....
why I get this error:
Object reference not set to an instance of an object.
when I try to access a LinkButton inside a Repeater as follows:
[Code]....
[Code]....
I need to change the row.forecolor = drawing.color.red.
in my gridview i have a STATUS field, its ItemTemplate is LABEL1 and its EditTemplate is DropDownList1.
on loading I have successfully changed the forecolor, but when I edit it gave me an error:
Object reference not set to an instance of an object.
I get the error:
Object reference not set to an instance of an object
Im facing a very complicated problem when i tried to view in browser. It shows the above error and i notice it highlights the line code below :
Line 733: Dim CurrentPoint As Double = CType(txt_point.Text, Double)
Stack Trace:
[Code]....
[Code]....
I'm getting this error with this code:
Protected Sub Repeater1_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.RepeaterItemEventArgs) Handles Repeater1.ItemDataBound
' display placeholder image if no imageId
Dim ltrImage1 As Literal = CType(e.Item.FindControl("Image1"), Literal)
Dim ltrImage2 As Literal = CType(e.Item.FindControl("Image2"), Literal)
Dim drv As DataRowView = CType(e.Item.DataItem, DataRowView)
If String.IsNullOrEmpty(drv("ImageId").ToString) Then
ltrImage1.Text = "<img src=""images/properties/x_thumb.gif"" alt="""" />"
ltrImage2.Visible = False
End If
End Sub
I want to set the image if no rows are returned.
[Code]....
I am getting error of in Foreach loop
[Code]....
How to resolve this situation or any other alternative to cum out of this problem.
i when i m set some value in data object. and create new object in form then new object contain previus value in it.
View 2 Repliesi am trying to post the results of my query to a label that is on a DataList however i keep getting this error? it doesnt like
"lbl.Text = cmd.ExecuteScalar().ToString();"
[Code]....
I get this error in the browser:
Code:
Thread was being aborted.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Threading.ThreadAbortException: Thread was being aborted.
Source Error:
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
Stack Trace:
[ThreadAbortException: Thread was being aborted.]
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +486
System.Web.ApplicationStepManager.ResumeSteps(Exception error) +501
System.Web.HttpApplication.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) +123
System.Web.HttpRuntime.ProcessRequestInternal(HttpWorkerRequest wr) +379
Version Information: Microsoft .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053
I have try{}catch(Exception ex){} in the right place:
Code:
protected void Button1_Click(object sender, EventArgs e)
{
try
{
// all processing occurs inside here
}
catch(Exception ex)
{
}
}
I even created a global.asax file and on the Application_Error event, I wrote a code that would email me the error (and i'm not getting an email regarding that error when I get the error shown above). I know for a fact that the thread is going inside the "try" statement because I send emails to myself whenever it finishes certain codes inside of it. So how come I'm getting that error in my browser instead of it being handled in my "catch" statement? I have two problems here, one, why is the exception not going to my "catch" statement, and two, why am I getting that error in the first place.
Note: my web app calls a webservice.
I am trying to implement the code URL...I have a database table with Integer type.Here is the running code line: Code in GridView:
<asp:TemplateField HeaderText="RegionNavn">
<ItemTemplate>
<%# Eval("RegionNavn")%>
</ItemTemplate>
<EditItemTemplate>
<asp:Label ID="lblRegionNavn" runat="server" Text='<%# Eval("RegionNavn")%>' Visible = "false"></asp:Label>
[code]...
On Edit Click, the DropDownList in the GridView brings the previously selected value.On Update Click, the error is: "System.FormatException: Input string was not in a correct format."
dCmd.Parameters.Add("@KystverketRegionID", SqlDbType.Int).Value = int.Parse(ddKystverketRegionID.SelectedValue);
When I use the following code:
ddlRegionNavn.DataTextField = "RegionNavn";
ddlRegionNavn.DataValueField = "RegionID"; // from RegionNavn to RegionID
On Edit Click, the DropDownList values in the GridView is not firing and the following error shows.Object reference not set to an instance of an object. How to implement the code when having a value of type Int ?