C# - Checking Whether Data Is Null?
Feb 10, 2011Is it best practice to check whether a value is null coming from a database even though there are constraints on the column which disallow nulls.
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Forms Data Controls :: Checking For Null On Aspx Page?
Jan 27, 2011checking for null on aspx page
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Forms Data Controls :: Checking Null Or Blank Text Boxes Prior To FormView Edit Update?
Jul 9, 2010I have a FormView that is loaded with a records from my DB. Some of the fields may be blank or null. I am trying to check the value of some of the text boxes to verify that the user has updated the fields prior to allowing a DB update from the Edit Template.
I can not seem to get the correct syntax on the if statment to check the value of the text box....
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Checking For Null Values
Jan 28, 2010protected void rptNavigation_ItemDataBound(object sender, System.Web.UI.WebControls.RepeaterItemEventArgs e){
if (!((e.Item.ItemType == ListItemType.AlternatingItem) || (e.Item.ItemType == ListItemType.Item)))
{return;
}string Name = string.Empty;
if (IsDBNull(e.Item.DataItem["FullName"])) {
Name = String.Empty;}
else {Name = (string)(e.Item.DataItem["FullName"]);}
Literal ltlLiteral = (Literal)(e.Item.FindControl("ltlLiteral"));
ltlLiteral.Text = Name.ToString();
I get error for IsDbNull - Error 1 The name 'IsDBNull' does not exist in the current context. What's the best way to check for null values returned from db? also I get errors on both lines where (e.Item.FindControl(ltlLiteral")); is present ERror: Cannot apply indexing with [] to an expression of type 'object'
Checking For Null List?
Jan 23, 2011I am making a class with an optional paramiter which will be a List<> paramiter. I want to set it's default value to null so I have used List<Params> Param = null. What am not 100% sure is checking the list to see if it was set to null or not. Is using:
if (Param == null)
Error While Checking Url - Key Can't Be Null
Sep 14, 2010.NET noob here (as in I know next to nothing, I'm trying to pick up some of the scraps left by my developer). Ok, I am getting this error on a number of my .aspx pages: Error while checking url '/': Key cannot be null. Parameter name: key Interestingly, I get this on my homepage on which the only .NET code is in the form of two includes, e.g: <% Response.WriteFile("/includes/footer.aspx") %> These includes in themselves only contain HTML, so I assume the issue can only be related to these or a configuration issue?
View 4 RepliesWeb Forms :: Checking For Null Value In Window.location.pathname
Feb 16, 2011I use the following code to get the file name out of the URL.
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This works fine if there is actually a page that shows up after a '/', I would also like to check for when there is nothing showingup after the '/'. My alert above shows nothing to be there, but how do I chack for the nothing. I have tried the folloiwng, but for some resaon it just ignores me. If I do an if statement, it doesn't pick up that there isn't anything there.
if (sPage = '') { alert(sPage);}
Even though there isn't anything there, it won't show the alert and acts as if there is actually something there.
Web Forms :: What's Simplest Method Of Checking For Null - Empty Text With Vb
Feb 20, 2011Is there one simple test that a person can do that covers all options where there could be a null, or "" value. When I google, I see so many options. I see:
if txtBox1.text IsNot nothing
if txtBox1.text.toString isNot nothing
if txtBox1.text <> ""
if txtBox1.text.toString <> ""
if isNull(txtBox1)
Is there on test that can cover them all?
Checking For Empty Array - Get Object Refernce Set To Null Error
Oct 19, 2010How do i check for empty array?
If I write
If Not ls_filename.Length = 0 then
....
End If
I get object refernce set to null error
DataSource Controls :: Checking From Null Values Comming From The Database?
Feb 11, 2010Is there a cleaner way to check for a null value comming from the database?
Right now i am doing this
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There has to be a better what than doing this on every row which could possibly be null
Forms Data Controls :: Displaying A Null Or Empty Cell For A Null Datetime Database Value In Gridview?
Dec 6, 2010I have setup my business object to have a create_date and edit_date members both datetime datatypes. My company want to display the create_date and edit_date fields in a gridview for each transaction. The problem i have is that after insterting a record it will have a valid create_date but no edit_date and when displayed in the gridview it defaults to datetime.minvalue (My default). How on earth do i show an empty field in my gridview for a null datetime field in the database?
I am using similar architecture to the Imar Spaanjaars example of a tiered solution. With a few small tweeks it has worked well for me for ages. I am passing a List<Database> to my object datasource which connects to my gridview.
Forms Data Controls :: Checking IDataReader For Valid Data?
Aug 3, 2010I'm populating a DataList using the IDataReader object and it works fine it the reader contains data. If the data is not present it displays nothing. I want to capture that situation and insert a verbiage such as "No data" or something like that. I've tried to test the datareader for various conditions such as Null, String.Empty, or plain " " but nothing worked. Is there a way to make this happen? Below is my code sample for your review.EJM.Note: It has to be done programatically as I'm building this for a web part.
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ADO.NET :: Checking For Valid Related Table Data In EF?
Nov 7, 2010I've always been a bit unsure how to check for the existance of properly referenced table data.
In my situation I have various tables related to each other in many-to-one relationships where the "1" side can be deleted without the reference fields on the "many" side being updated (nulled).
I have FK relationships set up in my MS SQL server database but have turned off the FK constraint enforcement (and cascading update/delete) so that I can delete records from the "1" side but leave the keys for those deleted records in the records on the "many" side. This is something I really need to do for my web app design.
Forms Data Controls :: Checking The Value Of A Boundfield?
Sep 10, 2010in my gridview i have a list of names that are bound.
in my aspx i have a list of names that i can select from.
i want to see if each selected name is already in the grid.
something like
if (li.Value == row.FindControl("Name").ToString())
Forms Data Controls :: Checking If GridView Has Data?
Dec 9, 2010I have a textbox, when ab OrderNo is entered in the textbox 3 GridViews are generated.
GridView1 has general data about the order
GridView2 has data about the items on the order
GridView3 has data about reserved/back order items on the order. GridView3 only has data if the order has items reserved or on back order.
Is it a way to check if the GridView3 has data or not?
I have tried
If GridView3 isnot Nothing then
'gets some data from GridView3
End If
But does not work. The code still goes inside the code block and returns an error when finding no data...
Forms Data Controls :: Checking Username In Database
Apr 30, 2010how to check if a particular data in the database already, for example, i want to check if a username already exist in database, then the user cant choose that username.
View 6 RepliesWeb Forms :: Appointment Validation Checking And Data Inserting
Sep 18, 2010I am beginner of asp.net and c#Currently i doing appointment website and need suggestions/ ideas. I have create a simple web form with Calender Control as picture below enable users to select date and time. At the calender control, i have set that users can only select tuesday and thursday every month using DayRender. After that i put a DropDownList to display the time.Next step, i want to store the data into database, for example UserA make appointment on Date 21 September 2010, Time 1100 and make it unavailable for other bookings. When UserB makes appointment on same Date and Time, it will display information that the slot is booked/unavailable. To implement this, what approach should i take?
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Keep That Password Encrypted In Code While Checking It Against A Data Store?
Jan 18, 2011Even with https enabled, you can write a password to the event log in code-behind. Any way to keep that password encrypted in code while you're checking it against a data store?
(using Login control)
(couldn't add comment to Andrew's answer, so I'm putting it here)
NTLM uses the username/password of the machine the user is logged into right? For this, I was thinking using ActiveDirectory on the server as the data store. It would have a diferrent un/pw than what the user is currently signed in to their machine as.
DataSource Controls :: Data Retrieving And Checking Queries?
Jul 28, 2010I'm currently working on a FOREX Live Trading project that I'm implementing.
I already have a database that stores the CURRENCY PAIR, BUY/SELL, PRICE AND QTY.
But I have a huge problem.
Scenario that is:
A person BUYS EUR/USD at a PRICE of 1.29900 @ quantity 100,000. (This will be recorded in the database table)
Then he BUYS EUR/USD at a PRICE of 1.29950 @ quantity 100,000. (This will then be recorded in the database also)
Then he decides to SELL his EUR/USD at a PRICE of 1.31000 @ quantity 200,000 all out. (How can I check from the database if he previously had make a transaction of BUY/SELL, so that I can do my necessary calculations for the P/L Statement)
Forms Data Controls :: Checking Row Status In Gridview?
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View 3 RepliesForms Data Controls :: Checking Values In Gridview?
Jan 24, 2011I'm using C# and SQL Server. I have one gridview which contain 3 columns "ID, COMPLETED (either yes or no), BY (adminID that completed)" and adminID can be null.
If user selected "yes" in COMPLETED column then how can I make sure that adminID in BY column is NOT empty or adminID entered is EXIST in database.
Forms Data Controls :: Checking A Value In A Method Before It's Inserted (Formview C#)
Nov 18, 2010I've been pickling my brain trying to do this for a couple of days but to no avail. I have the following in "FormView1" which I'm just using in insert mode:
<td class="style4">
<asp:TextBox ID="urlTextBox" runat="server" Text='<%# Bind("url") %>' CausesValidation="True" Width="200px" />
</td>
I'd like the contents (i.e. whatever the user wants to insert) to be passed to a method where it will be checked against any existing values in the database.
Forms Data Controls :: Checking The Required Field By Javascript?
Aug 10, 2010I have some controls on the asp.net page that can be required on certain senario and can be not required on others.
So we enable/disable them dinamaically depending on the current transactions.
Now I am thinking of a way where I can check the required field by Javascript on the click event of save button. Remember control not be required at all time.
Forms Data Controls :: Checking Last Updated Rows In Gridview?
Mar 24, 2011I need to know how to check last updated rows in Gridview.
View 2 RepliesForms Data Controls :: Accessing And Checking A Checkbox During ItemUpdate On A ListView
Nov 15, 2010I have the listview as bellow:
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