473,729 Members | 2,164 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

How to detect NULL value with cmd.ExecuteScal ar();

Hi -

I need to detect when the ExecuteScalar() method of the cmd object returns
NULL. I have tried the below code, however, it always returns false (this is
to say, that ExecuteScalar never returns NULL when in fact it does):

cmd.CommandText = "...SQL String goes here...";
cmd.CommandType = CommandType.Tex t;
if (cmd.ExecuteSca lar() == System.DBNull.V alue)
iScorecardId = 1;
else
iScorecardId = Convert.ToInt32 (cmd.ExecuteSca lar()) + 1;

Is there another way to check if ExecuteScalar returns NULL?

Thanks,
Nov 19 '05 #1
3 10149
On Wed, 06 Jul 2005 09:35:12 -0700, charliewest wrote:
Hi -

I need to detect when the ExecuteScalar() method of the cmd object returns
NULL. I have tried the below code, however, it always returns false (this is
to say, that ExecuteScalar never returns NULL when in fact it does):

cmd.CommandText = "...SQL String goes here...";
cmd.CommandType = CommandType.Tex t;
if (cmd.ExecuteSca lar() == System.DBNull.V alue)
iScorecardId = 1;
else
iScorecardId = Convert.ToInt32 (cmd.ExecuteSca lar()) + 1;

Is there another way to check if ExecuteScalar returns NULL?

Thanks,

try IsDbNull

Nov 19 '05 #2
Do you know what the equivalent of the *IsDBNull* function is for C#?

Thanks,

"intrader" wrote:
On Wed, 06 Jul 2005 09:35:12 -0700, charliewest wrote:
Hi -

I need to detect when the ExecuteScalar() method of the cmd object returns
NULL. I have tried the below code, however, it always returns false (this is
to say, that ExecuteScalar never returns NULL when in fact it does):

cmd.CommandText = "...SQL String goes here...";
cmd.CommandType = CommandType.Tex t;
if (cmd.ExecuteSca lar() == System.DBNull.V alue)
iScorecardId = 1;
else
iScorecardId = Convert.ToInt32 (cmd.ExecuteSca lar()) + 1;

Is there another way to check if ExecuteScalar returns NULL?

Thanks,

try IsDbNull

Nov 19 '05 #3
charliewest wrote:
Do you know what the equivalent of the *IsDBNull* function is for C#?


val == DbNull.Value

or

val is DbNull
Hans Kesting
Nov 19 '05 #4

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

1
1948
by: James A | last post by:
A particular item in my listbox is null. The field is of type currency. I'm running Access 2000 - SP3 When I use the Isnull(orderitems.column(12,12)) it does not detect it. Also, if i use the nz function it does not detect it either.
1
3634
by: Matt | last post by:
I could use some help dealing with null blobs. I'm returning a transaction from an Image BLOB field in SQL Server 2000 using C#. If the transaction exists the value is returned with out trouble, but because the ID can exist without having a value in the Image column the returned value is NULL and the code can't handle it and I receive this error when the Stored Procedure's value is returned (the line of code is marked with "**HERE**": ...
15
29279
by: TC | last post by:
What does it mean for an integer to have a null value? I am trying to use the DataView.Find method. That method has an integer return type which contains the "index of the row in the DataView containing the sort key value specified; otherwise a null value if the sort key value does not exist." By "null value", does it mean System.DBNull? (I thought only objects could evaluate to System.DBNull.) How can I test whether an integer variable...
8
22336
by: Earl | last post by:
What's the best way to check for null on an ExecuteScalar? The following would fire the command twice: if (cmd.ExecuteScalar() != null) { intContactID = Convert.ToInt32(cmd.ExecuteScalar()); }
1
14519
by: js | last post by:
I am using the following C# code and T-SQL to get result object from a SQL Server database. When my application runs, the ExecuteScalar returns "10/24/2006 2:00:00 PM" if inserting a duplicated record. It returns null for all other conditions. Does anyone know why? Does anyone know how to get the output value? Thanks. ------ C# ----- aryParams = {'10/24/2006 2pm', '10/26/2006 3pm', 2821077, null}; object oRtnObject = null;...
2
3347
by: Manikandan | last post by:
Hi, I have a table with following data Tablename:details No(varchar) Name(varchar) Updated(Datetime) 1 mm 10/10/2006 2 nn 02/12/2005 3 kk NULL I'm using executescalar to get the updated values from the table
1
5735
by: Manikandan | last post by:
Hi, I have a table with following data Tablename:details No(varchar) Name(varchar) Updated(Datetime) 1 mm 10/10/2006 2 nn 02/12/2005 3 kk NULL I'm using executescalar to get the updated values from the table
3
5002
by: bogdan | last post by:
Hi, I have a stored procedure that returns a single value. Example: SELECT @RowCount = COUNT(*) FROM t WHERE RETURN @RowCount I created a data set, table adapter, and adapter's method configured for the stored proc and as returning a single value. The wizard created an adapter method that calls SqlCommand.ExecuteScalar(). The problem is that
2
14658
by: qwedster | last post by:
Folk! How to programattically check if null value exists in database table (using stored procedure)? I know it's possble in the Query Analyzer (see last SQL query batch statements)? But how can I pass null value as parameter to the database stored procedure programattically using C#? Although I can check for empty column (the following code passes string.Empty as parameter but how to pass null value?), I cannot check for null value...
0
8764
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
0
9428
Oralloy
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. Here is my compilation command: g++-12 -std=c++20 -Wnarrowing bit_field.cpp Here is the code in...
0
9289
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth. The Art of Business Website Design Your website is...
1
9210
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
0
9156
tracyyun
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the choice of these technologies. I'm particularly interested in Zigbee because I've heard it does some...
1
6722
isladogs
by: isladogs | last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules. He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms. Adolph will...
0
6026
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert into image. Globals.ThisAddIn.Application.ActiveDocument.Select();...
1
3242
by: 6302768590 | last post by:
Hai team i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
2
2694
muto222
by: muto222 | last post by:
How can i add a mobile payment intergratation into php mysql website.

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.