have a look at my code below and tell me where i am going wrong.
case "particulars.aspx":
dt = JobCardManager.GetParticularsByJobId(id);
hidJobId.Value = id.ToString();
if (dt != null && dt.Rows.Count > 0)
{
gvParticulars.DataSource = dt;
gvParticulars.DataBind();
else
[code]...
environment: VS2008, MySQL 5.1.45, .net Connector 6.2.2
Error msg:
NoNullAllowedException: Column 'idNames' does not allow nulls.
The MySQL DB has on "idNames" (Primary Key) a tick-mark for: primary Key, Not Null, Auto-Increment Also: I can add/retrieve records via the 'MySQL Query Browser'; I see the data via VS2008 'Preview Data'!
As said in the comment below; when the 'idNames' is explicitely given the rows.add works fine. So it seems that I miss something around the 'auto-increment' business!
[code].....
Is it possible to allow repeated nulls on a column with a unique constraint? This column will won't always be populated with data upon insert, a condition must be met before the value is update. Once updated, it needs to be unique. Do I need to assign a temporary, random value or
View 1 RepliesI have an Edit View with a bunch of fields, some non-required. If the user decides not to fill them in, thats fine and it gets saved to the database as nulls (nullable fields).
The problem is when the controller redirects to the Details page and tries to render these null objects in labels using LabelFor(Model.SomeNonRequiredField)
Where/How should i be handling "acceptable" nulls?
Right now in my service layer im manually setting these nulls to String.empty before committing to the db, but now its saving it as an empty character instead of null - something like "SetDefaultValuesForNonRequiredFields(myObject)"
Caller to Draw.cshtml
if (errors == false)
{
PageData["Range"] = zoom;
PageData["StartReal"] = startRe;
PageData["StartImaginary"] = startIm;
PageData["StartColor"] = startColor;
PageData["N"] = N;
PageData["SizePic"] = sizePic;
@:<img src="@Href("Draw.cshtml")" />;
}
Here all variables have a value, however when arriving in Draw.cshtml the PageData all pass as null.
Draw.cshtml
@{
var zoom = PageData["Range"];
var startRe = PageData["StartReal"];
var startIm = PageData["StartImaginary"];
var startColor = PageData["StartColor"];
var N = PageData["N"];
var sizePic = PageData["SizePic"];
Bitmap bitmap = new Bitmap(sizePic, sizePic);
Graphics g = Graphics.FromImage(bitmap);
Pen myPen = new Pen(Color.Red);
juliaset(zoom, startRe, startIm, startColor, N, sizePic, g, myPen);
Response.ContentType = "image/jpeg";
Response.AddHeader("content-disposition", "inline; filename=test.jpg");
bitmap.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);
g.Dispose();
bitmap.Dispose();
myPen.Dispose();
}
I am using a cursor to iterate through a small set of record (28), perform some maths on each record and then update the record / row.
The problem is the cursor pulls in all nulls for every field in every row
It also gives me 28 rows, 28 times (see below)
[code]......
I have a situation where a query returns ~20 columns, but at any given execution only 5 of the 20 will have non-NULL values. The remaining 15 will contain null for every row in those columns.
I need to figure out which of the 5 columns have values. I am using a SqlCommand. How would I best approach figuring out these 5 columns?
I am working on a legacy application. It uses custom MVC framework and Windows Communication Framework service to bridge the Presentation layer with the rest of the application (i'll call this AppServer).
Every Entity in the AppServer inherits from BaseEntity which contains the method:
[Code]....
As you can see:
if the personObject was not null, but the ContactAddress was, [which is exactly what happens in the construction of a PersonObject in the event that no contact details are provided (hence they are not present in the HashTable and dont get created)] then the code will fail with a null reference exception.
SO:
Is there a fundamental flaw in the way that objects are getting created? It would be easy to point the finger in this direction, however, im sure there must have been some reason for the original architect to choose not to instantiate an empty ContactAddress object every time a Person object is referenced - EG if in a particular Presention->AppServer Request/Response cycle we only want a person's login details - we wouldn't care about the ContactDetails.
FINALLY MY QUESTION:
Is there a clean way to check for null objects within an aggregation, without doing something like:
if(Parent!=null)
if(Parent.child!= null)
if(Parent.child.child != null)
It just looks messy and it seems such a common problem, im sure there would be a better way of doing things.
I'm converting my application from using System.Data.OracleClient to Oracle.DataAccess.Client and I've noticed some weird behavior.
I am calling a stored procedure that sets an output parameter value. Under some circumstances, a null value gets assigned to this value and I need to detect it.
Here's how I'm declaring it using ODP.net:
cmd.Parameters.Add("p_status", OracleDbType.VarChar2, 200, DBNull.Value, ParameterDirection.Output)
The old Microsoft driver for Oracle would read the value as an empty string. However, ODP is returning a value {null} (per Visual Studio's debugger), which is not equivalent to null, DBNull.Value, nor an empty string. As a result, the code doesn't branch correctly now.
how to sort a datatable (dataview) so that the second column is ascending but nulls are last.
I'm trying to do the following Date1 ASC, DATE2 ASC (but if DATE2 is null it is last in this Date1 group)
Note: Date1 can never be null so a Date2 that is null should still be grouped in with its Date1.
I'm looking to find some command or control that will change fields in a detailsview insert a 0 if there was no data inserted into them. Some example code from my boundfield is:
<asp:BoundField DataField="Assignment_Travel_Time"
I have a Listview with a LinqDataSource. I am allocating a resoure called Bladder Scanners to clinicians on the day selected. The field in the database, 'Allocated_Bladder_Scanner_Id', allows nulls. The 'nullable' property of the field in the dbml is set to allow nulls.In the edit template, I have an unbound dropdownlist (drpBladderScannerDropdown) with an 'empty string' item added to cater for nulls, and
AppendDataBoundItems="true".In order to show only bladder scanners which have not yet been allocated on the selected day, I am databinding the dropdownlist to a dictionary of unallocated bladder scanners in the ItemDataBound event. I then add the currently selected bladder scanner as a listitem and set it as the selected item. So far, so good, all works well. However, if the clinician has a bladder scanner currently allocated, and then the user elects to not allocate the clinician a bladder scanner on that day by selecting 'Nothing' from the dropdownlist, the LinqDataSource fails to update the field. It does not throw an exception, it just doesn't set the field to nulls. In ItemUpdating I have the following code:
[Code]....
I have been struggling with an issue with the Detailsview that I'm using only sending null values to my sqldatasource update. I have seen people on the forums with this problem before but none with my specifics. Essentially, I'm creating a master/details scenario but using ajax updatepanels. A Gridview holds the master records and upon selection of that record the Detailsview is populated and brought up in a modal box. This works fine to display the data in the Detailsview. But upon update all nulls are sent back. I've evaluated the NewValues collection in the Detailsview OnItemUpdating event, and see all nulls. I read a posthere that talks about the KB article KB941155; which states a problem with .NET not being able to find a bound control in template situations:http://support.microsoft.com/kb/941155I wasn't sure if this applied to me since I am using Master pages. A couple of other notes. I am using BoundFields in my Detailsview, as well as a sqldatasource with a stored procedure updatecommandtype. The DataKeyNames are being set correctly as well.
View 6 RepliesMy filter Expression was working fine with filtering by Control Parameters.When I added the Phone Parameter it went nuts - with the Phone Parameter the GridView just Comes out blank upon loading the page (without it would show Select * from Individuals)Is it because the phone field is populated with numbers? Don't get it.... In the SQL server the 'phone' field is set to 'varchar(30)' and nulls are allowed.here is my code:
[Code]....
I am looking to sort a column on my gridview by simply clicking on the column rather than clicking on the column header. In the design I have been given, the column header will not be shown, and I need to be able to give the user to sort this column, by simply just clicking any where on the column.
View 2 RepliesI want to copy data from a table[tblExcel][No.of columns:2] to another table[ev_event] which has 5 columns, 2 columns from the another table, 3 columns from user defined value
[code].....
I'm currently working on a small project and therefore created a gridview, including one bit column which has been linked with a checkbox in both the itemtemplate as the edititemtemplate (autopostback = true).Databinding for these two checkboxes has been linked (two-way) to the bit column.Now I want to display the gridview to end-users. They should be able to just click on the checkbox so they value in the database column gets changed as well (as I want to run update queries behind it), but not passing via the command column 'EDIT'.=> problem I'm having now is that the bit column in the database doesn't get updated.
View 3 RepliesI'm currectly tryin to access a specific value in my database in a specific column. I'm tryin to use the primary key of the table to access the actual value in the row of that ID.
The current code:
[Code]....
Just iterates through the table and looking for any row with the boolean 'checkin' value is True, then it takes the 'id' value of that row and stores it into an array. Is there a way that I can access a another entry, and only that entry, in the table with the 'id' stored in the array?
Like if my data base contained and int, primarykey, `id` value, a boolean, `checkedin` value, and a `time` value, is there a way to access, lets say, the row with `id` equalling 3 and and the checkIn value from that row?
want to display gridview column heading when mouse over to the particular column in the gridview.
View 9 Replies[Code]....
Stacked-column chart has inconsistent column segment widths
How to handle this error
"An explicit value for the identity column in table 'UserActivation' can only be specified when a column list is used and IDENTITY_INSERT is ON."
I have a table converted from Access and the identity keys were lost. Now I need to make the id column the identity column, but it already has a lot of null values, how do I auto generate integer values for the null rows? The row ids are incremented, so if there is a way to auto increment the ids
View 7 Repliesi am making a website and i get a requirement that in GridView or ListView whatever control you used but the column is dragable means the order of the column can be change by drag and drop.Along with that i want to give option to the client that add more column if he check mark some column then that column should be added client side.So i am looking for some dll in ASP.NEt or Jquery for <table> Operation or javascript anything help me out
View 1 RepliesI have a 3 column layout using table-less design.
[code]....
The CSS:
#left {width: 200px;float:left;display:inline;}
#content {width: 600px;float:left;display:inline;padding: 0 10px;}
#right {width: 160px;float:left;display:inline;}
I am using a web application, and I can't change the layout. By can't change, I mean the div's with left/content/right cannot be removed.
On some pages, both the left and right columns are completely empty. And I want the #content div to expand more than the 600px.
is this possible, without altering the HTML?
How to add a button at first column of gridview and get cell value in another column?
For example, add a button named it as "Click me". Once user clicks will get third column cell's (ID) value.