Why following Code giving Nullable Error, it should converted to int right?int? abc=Session["test"] as int;t be used with a reference type or nullable type ('int' is a non-nullable value type)
View 9 RepliesI am making a website to store invoices so i can mail them to clients. So i got a table for clients, invoices and one with invoice products/services. When an invoice has no products/services added to them and it returns null i get the error "the null value cannot be assigned to a member with type System.Decimal which is a non-nullable value type."
I just started with linq. Before i always used mysql. Mostly i just had to call data from 1 table so forgive me if my linq query isn't really correct.
Dim invoices = From i In db.invoices _
Group Join p In db.products On i.id Equals p.invoiceId Into invoiceProducts = Group _
Select New With {i.client.naam, i.titel, (From iP In invoiceProducts Select iP.prijs).Sum}
i show the client's name, the title of the invoice and the total amount the clients will need to pay for products and services.
I am LINQ querrying against a datatable. However, I am unsuccessfull with catching null values. Here is my code that is giving me the following error.
[Code]....
I am checking to see if minperc is null. However to check that it still is trying to convert the value to double. Cant figure out a way around it. Here is the error: Cannot cast DBNull.Value to type 'System.Double'. Please use a nullable type.
I am little bit confused in value type and ref. type memory allocation.
Consider following case:
public struct Employee
{
public int Emp_no;
public string Emp_name;
};
//Createing object of struct
Employee objEmp = new Employee;
objEmp.Emp_no = 1012;
objEmp.Emp_name = "emp name";
So I have query regarding :
Q1. 'struct' is a value type and 'string' is reference type of data type. Then if I use 'objEmp.Emp_name' is stored where? The location is in heap or in stack memory? What type of this 'Emp_name' variable?
Q2. If I run garbage collection explicitly then what will happen with 'objEmp' object?
Im trying to bind a list with datetime objects to my repeater.
if (e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.Item)
{
DateTime actualDate = e.Item.DataItem as DateTime;
}
When I want access the itemdatabound event on the repeater Then I get an errormessage which says that DateTime is a valuetype and not a reference type.My solution is that a wrap the datetime in a custom object (reference type) and pass that to the repeater datasource instead of the datetime. But Im wondering if there are other solutions where the repeater takes valuetypes (DateTime objects).
Is string a reference type or a value type?
View 3 RepliesI want to convert the following SQL line to LINQ :
[Code]....
I have (or so I think!) a simple problem.
I will greatly simplify my model to speed this along.
I have a model class lets call it item:
public class Item
{
[Required(ErrorMessage="Must indicate if product is to be tracked by serial number.")]
public bool TrackedBySerial { get; set; }
}
I have an "Add" view where I create a DropDownList like so:
<%= Html.DropDownListFor(model=>model.TrackedBySerial, new SelectList(new List<object> {null,true,false},null),"Select One") %>
<%= Html.ValidationMessageFor(model => model.TrackedBySerial) %>
My problem is that unless I create my boolean value in the model to be a nullable type, I can't force the blank default value.
If I use the Html.DropDownList() instead of DropDownListFor() , is there any way for me to use ModelState.IsValid -- or do I need to mix my own custom validation in my controller as well?
Update: So I got the functionality I was looking for, its just a bit more verbose than I'd have liked. Is there a better way to do this?
Controller:
[HttpPost]
public ActionResult Add(InventoryItem newItem)
{
try
{
//get the selected form value
string formVal = Request.Form["TrackBySerial"];
//convert to true, false, or null
bool? selectedValue = TryParseNullable.TryParseNullableBool(formVal);
//if there is no value, add an error
if (!selectedValue.HasValue).....
view:
<div class="editor-field">
<%=Html.DropDownList("TrackBySerial","- Select One- ") %>
<%=Html.ValidationMessage("TrackBySerial") %>
<%= Html.ValidationMessageFor(model => model.TrackedBySerial) %>
</div>
I have a question regarding routing and an issue that I am currently having in my application. I have an action, providers/List/, which accepts two parameters, a zipCode and a page value for paging results. I have defined this route as follows in my global.asax, /providers/{zipCode}/{page}
I have created another action in this controller, Dashboard, which does not expect any parameters, so I am assuming that the route would ultimately be /providers/dashboard, if I am not mistaken. What is happening is that for some reason I am getting a routing error regarding zipCode not being a non-nullable type. It makes me think that the first action's route is what is getting hit instead of going to the dashboard action. I am sure that it has something to do with the route entry that I have made in my global.asax file.
When i click on the page that represents a controller the following error was displayed:-
"The null value cannot be assigned to a member with type System.Int32 which is a non-nullable value type"
On this link of code
var articleapproval = articletyperepository.FindAllArticlesRequireMyApproval().ToList();
while the FindAllArticlesRequireMyApproval execute the following LINQ statement :-
var articleapproval= articletyperepository.FindAllArticlesRequireMyApproval().ToList();
where this methods calls the following LINQ statement:-
My code:
[Code]....
If the value is null writes out that error.How to check if the value is null? And if the value is null, I want to store + 1
I am trying to call web reference "A" in an application.
The web reference "A" will then call a function in another web reference "B" through HTTPS connection (require certificate).
Then I keep getting the following error:
An unhandled exception of type 'System.Web.Services.Protocols.SoapException' occurred in System.Web.Services.dll
I have a problem:
I've created usual Controller and View(Edit view) for editing my Entity (EntityFramework)
Here is view example:
<div class="editor-field">
@Html.EditorFor(model => model.BirthDate)
@Html.ValidationMessageFor(model => model.BirthDate)
</div>
BirthDate is Nullable<DateTime>
but during loading my View I get this exception
The model item passed into the dictionary is null, but this dictionary requires a non-null model item of type 'System.DateTime'.
That's because of BirthDate is null in database but it is nullable and I expect that it just leaves the filed empty.
And I have Shared EditorTemplate:
@model System.Nullable<System.DateTime>
@if (Model.HasValue)
I am not sure if I have found the right forum for this one.
the problem is:
I have a .licx file in my rootfolder.
I am getting the error:
Error 53 Unable to resolve type ' <add type="TabStrip" version="7.0" />' C:inetpubwwwrootCrop_ApplicationCrop_Applicationeo_web.licx 7 Crop_Application
,which I get for all the types that are in the xml file(i just gave one of them).
A friend told me that I have to add the type .licx in the MIME type in the IIS .
The problem is that I find the MIME type, I add the extension type .licx but I do not know the MIME type for .licx
I recently moved my class based on IUnityResolver from the mvc3 project (where I tested it), to a class library (which references all five Unity dll's. I'm getting the following error, why? Are there other dependencies for which I am unaware?The type or namespace name 'IUnityContainer'...are you missing an assembly or reference?
View 3 RepliesI have a webservice - called MyCompany.WebService1
I reference this using a web reference in my ASP.net web application.
Theres a method called "GetDeal" in this web service, that returns a "Deal" Object.
The deal object currently looks (for example) like this:
[code]....
This class is in a different assembly: MyCompany.Model
The web service references this assembly.
In my web app, I can call the GetDeal method. This returns Service1.Deal (service1 is just the name of the web reference)
I can access both properties above. I have now changed the Deal class, and added a couple more properties.
However, I can't see these new properties in my web application. I've updated the web service in the web application. I rebuilt the web service several times, tried removing the MyCompany.Model reference and re-addding it etc...
I can't figure out what has changed... This was working - I have changed the model before, and it's updated the reference correctly...
I have a FormView that allows a user to register for a company event. I want to do a couple of things with this form.
1. I need to write this data to a MS SQL database
2. I need to send an email confirmation of their registration to their email.
I know how to do both of these things, but i am having trouble doing both at the same time.
It would be nice if I could do it in one click, but I coded it into two pages to try to help simplify it.
The first page allows the user to input their information into a formview and when they click the submit button, it places those answers into session variables:
[Code]....
[Code]....
The Second page confirms the users information by taking those session variables and placing them into labels:
[Code]....
[Code]....
However, after I place information into the formview on the first page, it throws up this error:
"Conversion from type 'TextBox' to type 'String' is not valid".
I'm trying to create a validation layer that will contain methods to validate all my objects (in my Business Objects layer) .. but when I try to reference both the validation and business objects to each other I get a circular dependency error .. so I've decided to create a new layer (BLL) to validate the objects for me and I'll be able to reference both the validation and the object layers.
so I want to build some kind of class/interface -I don't know what fits more- to be like a generic type or a parent type that my method could accept it as a parameter and check for it's Name/ID property. Instead of defining a new method overload for each object type I have
Simplification
I have this error "The given value of type String from the data source cannot be converted to type datetime of the specified target column." when I used sqlbulkcopy to do the transaction
Here is my code:
[code]....
I have built a dataset named Transaction_Time.I called it on Page_Load
Transaction_Time tranTme = new Transaction_Time();
put it in the session.
Session["Transaction"] = tranTme;
Then I call that session and cast to dataset.
DataSet dstTranTime = (DataSet)Session["Transaction"];
I got the following error.Unable to cast object of type 'Transaction_Time' to type 'System.Data.DataSet'.
[InvalidCastException: Unable to cast object of type 'Transaction_Time' to type 'System.Data.DataSet'.]
Transaction_Time.Page_Load(Object sender, EventArgs e) in c:InetpubwwwrootWilliam29_11_2010Transaction_Time.aspx.cs:47
System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14
System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35
System.Web.UI.Control.OnLoad(EventArgs e) +99
System.Web.UI.Control.LoadRecursive() +50
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627
It is OK for some other pages. But for some page, it doesn't.
If I have a linq query that creates the anonymous type below:
select new
{
lf.id,
lf.name
lf.desc,
plf.childId
};
Is it possible to assign a specific type to one of the members? Specifically I would like to make lf.id a null-able int rather than an int...
i am using this code for send data to view
[Code]....
Controller e 'System.Collections.Generic.IEnumerable [Code]....
by this code i am render view
[Code]....
after run the application i got this error
Unable to cast object of type 'System.String' to type 'System.Collections.Generic.IEnumerable`1[BentaAccounting.Models.Repository.AllData]'.
My problem is that when I submit the form and returning my viewModel of type QuestionViewModel - the Type is null.
See code below.
[code]....
I'm trying to get a value from a database and I'm getting an error, see code below:
[Code]....
I get and error when I'm trying to convert the value out of the stored procedure to the string SNAME. Error is as follows:
'Conversion from type 'DBNull' to type 'String' is not valid.'
and the stored procedure is as follows:
[Code]....
I get the error - Conversion from type 'DBNull' to type 'Integer' is not valid. - on the line.....
Dim newid As Integer = e.Command.Parameters("@latestRowId").Value.........in vb code behind.
I have the identical code for another page with the exception of the field names and it works fine. The only thing I did differently, as far as I know, is I copied the asp and code behind from the page that works into this page and manually changed the field and table names. I don't know what the problem is. Does anyone see any problems?
[Code]....