Oledbdataadapter in backgroundworker

Question

1.00/5 (3 votes)

See more:

Helo,

I try to execute in my main form in the BackgroundWorker DoWork this code:

C#

try
            {
                bool pingResult = verificareInternet();
                if (pingResult == true)
                {
                    sendNotification[] dateNotificari = sendNotification.dateDeTrimisSms();
}
}

code for sendNotification:

C#

internal static sendNotification[] dateDeTrimisSms()
        {
            Program.Connection.CommandText = "SELECT * FROM tabelanotificari";
            DataTable dataFI = new DataTable();
            Program.Connection.FillDataTable(dataFI, true);

            return InterogariDB.Lista<sendNotification>(dataFI, delegate(DataRow rezultatTB)
            {
                return new sendNotification(rezultatTB);
            });

        }

C#

class sendNotification
    {
        public string PhoneNumber1 { get; set; }
        public string PhoneNumber2 { get; set; }
        public string PhoneNumber3 { get; set; }
        public DateTime StartDate { get; set; }
        public DateTime EndDate { get; set; }
        public string Name { get; set; }
        public int ContractId { get; set; }
        public string TelefonPc { get; set; }
        public string CNP { get; set; }

        public int status_notificari  { get; set; }
        public DateTime data_notificari { get; set; }
        public int ultima_notificare { get; set; }

        
        public sendNotification(DataRow dateDeTrimisNotificari)
        {
            this.PhoneNumber1 = (string)dateDeTrimisNotificari["PhoneNumber1"];
            this.PhoneNumber2 = (string)dateDeTrimisNotificari["PhoneNumber2"];
            this.PhoneNumber3 = (string)dateDeTrimisNotificari["PhoneNumber3"];
            this.StartDate = (DateTime)dateDeTrimisNotificari["StartDate"];
            this.EndDate = (DateTime)dateDeTrimisNotificari["EndDate"];
            this.Name = (string)dateDeTrimisNotificari["Name"];
            this.ContractId = (int)dateDeTrimisNotificari["ContractId"];
            this.TelefonPc = (string)dateDeTrimisNotificari["TelefonPc"];
            this.CNP = (string)dateDeTrimisNotificari["CNP"];
        } }

If i execute the cod outside the BackgroundWorker the code run OK, but i get an error on:

C#

new OleDbDataAdapter(Command).Fill(Table);

Any sugestions?

What I have tried:

Execute the code outside the BackgroundWorker.

Posted 28-Apr-16 4:27am

aciobanita constantin

Updated 28-Apr-16 8:22am

v3

Add a Solution

Comments

Sascha Lefèvre 28-Apr-16 10:31am

"but i get an error" - please tell us the error message.

aciobanita constantin 28-Apr-16 14:09pm

Is an abstract error, null reference on new oledbadapder.fill

OriginalGriff 28-Apr-16 10:36am

Perhaps if you showed us the code that generates the error and the exact error message it would help.
The only mentions of OleDbDataAdapter are the in subject and the "I get get and error on" line.
Use the "Improve question" widget to edit your question and provide better information.

aciobanita constantin 28-Apr-16 14:11pm

The pice of code were I get the error is new oledbadapder.fill, and is a null reference, only inside the Beck round worker Dowork,

Philippe Mori 28-Apr-16 12:42pm

You won't get many vote of more than 1 point if you are to lazy to copy the error message you get.

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Answer 1 · 2016-04-28T08:22:00

"The pice of code were I get the error is new oledbadapder.fill, and is a null reference, only inside the Beck round worker Dowork,"
Which you don't show us, as I said before... :sigh:

But...it's a Null Reference Exception.
This is one of the most common problems we get asked, and it's also the one we are least equipped to answer, but you are most equipped to answer yourself.

Let me just explain what the error means: You have tried to use a variable, property, or a method return value but it contains null - which means that there is no instance of a class in the variable.
It's a bit like a pocket: you have a pocket in your shirt, which you use to hold a pen. If you reach into the pocket and find there isn't a pen there, you can't sign your name on a piece of paper - and you will get very funny looks if you try! The empty pocket is giving you a null value (no pen here!) so you can't do anything that you would normally do once you retrieved your pen. Why is it empty? That's the question - it may be that you forgot to pick up your pen when you left the house this morning, or possibly you left the pen in the pocket of yesterdays shirt when you took it off last night.

We can't tell, because we weren't there, and even more importantly, we can't even see your shirt, much less what is in the pocket!

Back to computers, and you have done the same thing, somehow - and we can't see your code, much less run it and find out what contains null when it shouldn't.
But you can - and Visual Studio will help you here. Run your program in the debugger and when it fails, VS will show you the line it found the problem on. You can then start looking at the various parts of it to see what value is null and start looking back through your code to find out why. So put a breakpoint at the beginning of the method containing the error line, and run your program from the start again. This time, VS will stop before the error, and let you examine what is going on by stepping through the code looking at your values.

But we can't do that - we don't have your code, we don't know how to use it if we did have it, we don't have your data. So try it - and see how much information you can find out!