How To Handle Null Fields In DetailsView Control Bound To TemplateFields
Dec 16, 2010
I am using the DetailsView Control to read a LastUpdatedDate field (which can be null until an update is performed) from the database. The LastUpdatedDate is of type DateTime saved in UTC. With the DetailsView control, I can use the NullDisplayText property of the boundfield to safely display an custom message. However, once converted to a template field, that property is lost. Now, how would I display that message if the field is null as I am also formatting the date for display to show in local time.
In the detailsview, I set a edit item template (a bounded dropdownlist control). But in database there are some data not set to a value (null). After clicking edit button in detailsview control I get the error about the value problem (Because after populating the dropdownlist, there is no item as null in it. )How to set dropdownlist selected index when the data is "null"?
I'm trying to use the DetailsView to make Updates. The problem is that it can't handle empty fields even though the underlying table field allows nulls.
I get a message like this if I change the "State" field to blank when doing an update
The parameterized query '(@Cust_ID int,@Cust_DL nvarchar(7),@DL_State nvarchar(2),@Last_N' expects the parameter '@State', which was not supplied.I'm using an object data source control which is calling the EditCustomer method in my Customer Class. I'm not sure how to fix this.
I have GridView control and assosiated DetailView control.
When the record form GridView is seleted, I am showing the details on DetailView.
I have set the Auto generated delete button to true. And now I want to delete the record when someone clicks the Delete button from DetailView control.
I've got a detailsview control on a page. The table that it interacts with has a DateTime column in it. This column is nullable, and a lot of the records have null for that value. In the EditItemTemplate I've got a calendar control. When I try to put the DetailsView into edit mode, I get the following error message:
System.InvalidCastException was unhandled by user code Message=Specified cast is not valid. Source=App_Web_srpmlyjd StackTrace: at ASP.entries_aspx.__DataBinding__control44(Object sender, EventArgs e) in c:inetpubwwwrootMediaLibraryEntries.aspx:line 103 at System.Web.UI.Control.DataBind(Boolean raiseOnDataBinding) at System.Web.UI.Control.DataBindChildren()
I am convinced that the problem is the null values in the DateTime column of the table. I've done some web searches on this, and some have suggested placing some dummy values into that column, but that seems more like a kludge, rather than a solution. How do I keep nulls in the table, and yet not have that preceeding error come up when a user tries to edit the selected record?
I have a GridView, and I want Column1 to be equal to datatable data (filled by a SqlDataAdapter). Then I have two other fields by the SqlDataAdapter (first name, last name), and I want to have those two fields combined to form Column2. I have a TemplateField for my GridView that combines the first name and last name with Eval()'s, but the GridView places this combined field TemplateField and puts it as the first column.
How can I do this so that TemplateField can go in between fields that are databound?
I'm hacking my way through ASP.Net WebForms, coming from VB.Net WinForms. I was hoping the transition would've been more seamless... it is not.
I have a GridView (Paging enabled) bound to a DataTable, filled with Joined tables from an Access 2000 DataBase.
The GridView and DetailsView are bound to the same DataTable.
In the GridView's SelectedIndexChanged Event I have the following:
vb.net Code:
' dtvSelected is the DetailsView' dgvJobTOF is the GridView Me.dtvSelected.PageIndex = Me.dgvJobTOF.SelectedIndex
When the page loads the first item in the GridView is also displayed in the DetailsView.
I've added a "Select" button in the GridView and when it is clicked the Data in the DetailsView remains the same regardless of the selected GridView row.
I have a query expression which I am binding to a GridView in Page_Load. The data I want to capture in the SelectedIndexChaned event is in a BoundField defined thus:
I'm trying to populate a date from a bound text field in a DetailsView. I keep getting a error when a DBNull is in the column. How do I avoid the DBNull when populating the text field.My code is as follows:
I just can't figure out how to approach this, but this is what I want, would be I have a database-table containing an XML-field. Using LinqToSql I succesfully bound this table to a GridView and a DetailsView control.ow I wrote a WebUserControl that renders a bunch of textboxes, and has a method 'Serialize' that returns the XElement-object that I can use in my codebehind to assign it to the LinqToSql-property to save it to database. It also has a public property 'Xml' (type string) that I can use to Bind() the xml-string from the database to it, so the WebUserControl can prefill it's textboxes.
I have a dropdownlist in the edititemtemplate of a detailsview. The dropdownlist is bound with an objectdatasource. The detailsview is bound to a seperate objectdatasource which connects it to the insert method. When the page loads the dropdownlist is bound properly. However, when I make a selection and select insert I get the following error: Could not find a property named 'DeptID' on the type specified by the DataObjectTypeName property in ObjectDataSource 'objCurrentProduct'. I've tried to remove the SelectedValue='<%# Bind("DeptID") %> attribute. I can then insert without an exception being thrown but the selected value of the dropdown is not recognized. Here is the code:
I am using a DetailsView component (dvExpertsData) bound to a SqlDataSource (sqldsExpert) with a field that has a ItemTemplate (Field[9]) with a checkbox component (chkbxAvailable) assigned to it. The idea is to have only this item updated out of all the data presented, so I do not have a requirement for editing an other data. sqldsExpert's SELECT query is a call to a stored procedure as is the UPDATE query.
I want to add boundfield to the Detailsview control at the run time. The data is coming from the dataset, which is fetching data from SqlDataAdapter. I tried using the following code
string st = "select * from tbrob,tbemp,tbcty,tbcmp where robfircod=" + TextBox1.Text.ToString() + " and robempcod=empcod and robctycod=ctycod and robcmpcod=cmpcod";
my problem is that i have a gridview that fetch the data from database .I added the linkbutton on gridview that redirect to next page but cant working becouse at run time i add a bound field on gridview to calculate the time. source code
Background: I'm populating lots of asp.net c# GridViews and ListViews from a database and subsequently users may export them to Excel. I want export as native Excel (not html). I can't use office automation, and I'm using JET which works fine. I have no control over users' machines. Question: When doing the export, you have to tell Jet what type each field is, in my case "text" (varchar) or "numeric" (double). The difference is that if you export a numeric column, the users can sum the data in Excel, where as strings are exported with a leading apostrophe and so are not much use in arithmetic.
Currently I parse the first data row of the Grid/ListView, check if each value is numeric or text, and assign a type to the column accordingly. That works, except for when I have something in the first column which looks numeric but in fact is a text string. I don't want to parse every row in order to be sure I have the correct data type as some of these exports are quite large. When I load the Grid/ListView from the database, the database certainly knows what type each field is. So my question is... how do I extract the type of the database item behind a a Grid/ListView item? I could explicitly code it as an attribute on the item, but that's duplicating information I already have, if only I can get to it. I know that where I have a DataTable then I can get the underlying type from that, but mostly I don't have tables handy, just the Grid/ListView. Note that Jet will throw if you try to insert an empty string into a nullable numeric column. The way to do this is to omit that column name from the insert statement, or output a zero.
I have an Objectdatasource configured with Select, Insert, Update & Delete queries in a Dataset. This datasource is linked to my Gridview. I do not require all fields in the table to be displayed or updated in my grid so i have turned off the Visible property on several.
However, when i go into Edit mode and trigger the UPDATE to the database table, i get NULL values updated in the columns i set False for the Visible property.
How can i remove these columns from the GridView and the Edit mode and still have them UPDATE with their current values instead of being overwritten with NULL's?
Is there anyway to have a detailsView auto Generate the fields in a Table.I am binding my detailsview to a datatable but only getting the first two fields ....
for eg i hav a datetime field called Completion date which temporarily has a null value and when i display the records using a gridview it displays a default date...how do i get rid of this default date.the completion Date gets entered at a later stage in the application following which the gridview should show this date....but initially it shouldn't show anything
What if a user hits my site with [URL]t rather than [URL] In other words, they do not specify a value for {id}. If they do not, I want to display a nice "Not Found" page, since they did not give an ID.Is there a more standard MVC framework way of handling this, rather than the code I presently use (see below), where I test accept a nullable int? and then for null? Surely there is a smoother way to handle this.
I have a problem while checking a hashtable value. In the code below I am storing 60 values in the hashtable "hash". One of the values is (or can be) Null. I am checking each entry against its corresponding entry in hashtable "hash1", to see if they match each other. If they don't match I want to check if the value in "hash" is Null, but I can't catch it - it's falling through the 'else' part). How can I overcome this problem?
I have been having trouble with this for a while now. I have a bound textbox within a Detailsview, to which I have added a RegularExpressionValidator (REV). The Regular Expression used is [a-zA-Z]*
After running the Web Form, the Edit button opens the fields. Any entries made cause the REV error msg to be displayed when the Update button is pressed, irrespective of the validation. The Update button continues to be displayed until the Cancel button is selected and the original record is returned to the screen replacing any entries.