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
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:-
I got the following error when i tried to insert a new record after the run my project, so what does this error indicates?
"{"Cannot insert explicit value for identity column in table 'Articles' when IDENTITY_INSERT is set to OFF."} System.Exception {System.Data.SqlClient.SqlException}
"
I 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 getting an exception on a linq to sql query:The null value cannot be assigned to a member with type System.DateTime which is a non-nullable value type.
[Code]...
I am writing unit tests for fluent Nhibernate, when I run the test in isloation it passes, but when I run multiple tests. or run the test more than once it starts failing with the message below System.ApplicationException : For property 'Id' expected '1' of type 'System.Int32' but got '2' of type 'System.Int32'
[TextFixture]
public void Can_Correctly_Map_Entity()
{
new PersistenceSpecification<UserProfile>(Session)
.CheckProperty(c => c.Id, 1)
.CheckProperty(c => c.UserName, "user")
.CheckProperty(c => c.Address1, "Address1")
.CheckProperty(c => c.Address2, "Address2")
}
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 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)
My designer.cs file of all the SQL tables is generated by LINQ-TO-SQL. The class and attribute in question is like this.
[global::System.Data.Linq.Mapping.TableAttribute(Name="dbo.Transfers")]
public
partial
class
Transfer :INotifyPropertyChanging,[code]...
I need to assign a null to the attribute so that the value 0 does not get save to the database.
I have following model class:
public class WebModel
{
public List<ArticleModel> Articles { get; set; }
}
public class ArticleModel
{
public int ID { get; set; }
public double ValueParam { get; set; }
}
Then I have the controller with the two actions:
[Authorize]
public ActionResult Index()
{
WebModel model = new WebModel();
ModelConverter.ConvertToModel(model, controller);
return View(model);
}
[Authorize]
[HttpPost]
[ValidateInput(false)]
public ActionResult Index(WebModel model, string saveButton)
{
ModelValidation.ValidateWebModel(model, ModelState);
if (ModelState.IsValid)
{
return RedirectToAction("Create", "Article");
}
ModelConverter.ConvertToModel(model, controller);
return View(model);
}
And this is my view:
<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Web.Models.WebModel>" %>
<asp:Content ID="Content1" ContentPlaceHolderID="MainContent" runat="server">
<%var controller = Session["controller"] as Web.Code.SessionController; %>
<%Html.BeginForm(); %>
<div>
<table width="100%">
<%foreach (var article in Model.Articles)
{%>
<tr style="text-align: right">
<td>
<%:Html.DropDownListFor(m=>m.Articles.FirstOrDefault(f=>f.ID == article.ID).ID, new SelectList(controller.CurrentProdukt.Articles.AsEnumerable(), "ID", "Name", article.ID)) %>
</td>
<td>
<%:Html.TextBoxFor(m => m.Articles.FirstOrDefault(f => f.ID == article.ID).ValueParam)%>
</td>
</tr>
<%} %>
</table>
</div>
<table style="width: 100%">
<tr>
<td>
<input type="submit" name="saveButton" value="Save" />
</td>
</tr>
</table>
<%Html.EndForm(); %>
</asp:Content>
If I press the submit button, I get to the second action method in the controller (the one with the HttpPost attribute). In this action, the object model itself is not null, but the "Articles" list inside is null.
i work with visual studio 2005 and asp net 2.0. i have a method method as this :
[Code]....
this problem is follow if i run the web method and don't enter a string and a int a receive this message : System.ArgumentException: Cannot convert to System.Int32. ok when i arrive in the method i can check if lists is empty but how i can do if int is NULL because i don't want to returns a error if people run my web method and don't enter the parameters.
Unable to cast object of type 'System.Web.UI.LiteralControl' to type 'System.Web.UI.WebControls.TextBox'.
[code]....
I want to do paging the API Membership without using the datacontrols, but I get this error "Unable to cast object of type '<TakeIterator>d__3a`1[System.Char]' to type 'System.Collections.IList'." when I do this,
[code]....
Basically, what I did is that: I have a table in SQL database and some of data fields allow null. I built Objectdatasource through dataset. When I built update page using dataset. It generate the following error before showing the update page correctly. It seems I have issue to retrieve the null value from the database through using objectdatasource through dataset. Any suggestions?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
View 6 RepliesI have defined an ODBC Command and ODBCdatareader as follows
OdbcConnection myConnection = new OdbcConnection(connectionString);
OdbcCommand myCommand = new OdbcCommand();
myCommand.Connection = myConnection;
myCommand.CommandText = "select UOPGM from GREG.TUSROPTF";
OdbcDataReader myReader;
myConnection.Open();
myReader = myCommand.ExecuteReader();
When I try to retreive from the reader as follows:
while (myReader.Read())
{
string someString = myReader["UOPGM"];
lstNames.Items.Add(someString);
}
I get the following error
Error reading the database. Unable to cast object of type 'System.Byte[]' to type 'System.String'."
I have also tried string someString = (string)myReader["UOPGM"]; to no avail
I am trying to write a table output from SQL database to a gridview/ Data List through an Object Data Source. I am a new starter and your help will be useful.
public List<Staff> GetStaff()
cmd.CommandType =
SqlConnection con =
new
SqlConnection(connectionstring);SqlCommand cmd =
new
[code]...
I am trying to upload a picture into database using FormView insertItemTemplate. FormView is bounded by objectdatasource.To upload, I placed FileUpload control inside insertItemTemplate.In table the dataType is image.Error:Object of type 'System.Boolean' cannot be converted to type 'System.Byte[]'.
View 3 RepliesWhy 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 Replies[Code]....
Above is my code. The error I'm get is, Unable to cast object of type 'System.DateTime' to type 'System.String'.
The column "To" and column "Subject" are strings and column "Receive" is DateTime. I can't made any changes in the database, so I need to write some code to handle casting a string to datetime or if statement as a work around.
Protected Sub FormView1_ItemCreated(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.FormViewCommandEventArgs) Handles FormView1.ItemCreated
Causes Unable to cast object of type 'System.EventArgs' to type 'System.Web.UI.WebControls.FormViewCommandEventArgs'.
The program (asp.net/vb) works fine with FormView1_ItemCommand and FormView1_ItemInserted events but strangely objects to FormView1_ItemCreated. Is it only a VC# event?
Unable to cast object of type 'System.String' to type 'System.Byte[]'....
on line #2
private void download(DataTable dt) { Byte[] bytes = (Byte[])dt.Rows[0]["FileData"];
Response.Buffer = true; Response.Charset = "";
[Code]....
System.InvalidCastException was unhandled by user code
Message=Unable to cast object of type 'System.Guid' to type 'System.String'.
Source=System.Data.Linq
System.Data.Linq.SqlClient.SqlProvider.System.Data.Linq.Provider.IProvider.Execut
Why am I getting this error on line:
sp.Price = Convert.ToDecimal(collection.GetValue("Price"));
sp is :
SPecials_Templates sp = new SPecials_Templates();
SPecials_Templates Defined:
[MetadataType(typeof(SPecials_TemplatesMetaData))]
public partial class SPecials_Templates
{
public class SPecials_TemplatesMetaData
{
[ScaffoldColumn(false)]
public object Key { get; set; }
[StringLength(50)]
public object Template_Name { get; set; }
[StringLength(12)]
public object Headline { get; set; }
[StringLength(12)]
public object headline2 { get; set; }
[StringLength(160)].......
I remember being told that you can add some syntax to the end of a statement that will do something if the field is null. Pretty vague, but I cant seem to find anything about it via google.
I definitely isnt how to set a field to be nullable. I know that.
Here is an example of what I want.
int? field1 = 0;
field1 = int.parse(string2); (where string2 is a passed value, that could be null)
I thought there was something you could put at ?? if it is a null, such as:
field1 = int.parse(string2) ??;
Or do I have to check every if every string2 is null before making that statement.
Can anyone reliably get the EDS to save a nullable column to the databse as a "null" when bound to any of the controls such as "FormView"?I have tried using several different UpdateParameters (Session, ControlParamater, Parameter, etc). I have tried setting "ConvertEmptyStringToNull" to true and leaving the property off entirely. Nothing works. On my "Inserts" it works fine.(I have made sure the column is set to nullable = true in the Entity Designer.....)
View 7 Replies
