asked on

Object reference not set to an instance of an object.

Hello,

I have a stredproc which returns an email address if it finds in the tabel. I use this returned email and to insert records to another tabel and if it doesn't find a macthing record i want to be able to give a message to the user who is using the app that there is no macthing record foun . however when it doesn't find one it says.

System.NullReferenceException: Object reference not set to an instance of an object.

how can i handle that?

thanks

2266180

you are probably using the returned email and since it is null, it throws that exception. do an
if (retEmail != null)
showmessage;
else
do whatever

If you can't figure it out, post that part of the code

jemigossaye

ASKER

here is the code. I tried what u suggested but no change

SqlCommand lo = new SqlCommand("UserGetEmail", conn);
lo.CommandType = CommandType.StoredProcedure;
lo.Parameters.Add("@Email", SqlDbType.NVarChar, 120).Value = alternateLogin;
conn.Open();
string LoEmail = lo.ExecuteScalar().ToString();

if (LoEmail != alternateLogin)
{
string LoInsert = ("INSERT INTO mms.dbo.user_inf (UserName,PasswordHint,UserAlternateLogin)" +
"Select Top 1 l.lo_login,'Email',l.email_address from INTRANET.dbo.lo_information l where l.email_address='" + (alternateLogin) + "' select scope_identity()");
SqlCommand LoCommand = new SqlCommand(LoInsert, conn);
}
else
{
DisplayMessage.Show("There was no mathcing email address in the data base. Make sure you have inserted the correct one");
}

2266180

what is the line with error?

jemigossaye

ASKER

the line error is caused here :
string LoEmail = lo.ExecuteScalar().ToString(); when there is no email found
saying that Object reference not set to an instance of an object.

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2266180

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jemigossaye

ASKER

what do u mean the need type here like the class it self

2266180

I mean the class of "lo.ExecuteScalar()". The function returns a reference to a certain class; probably object. I am not sure and don't have an IDE handy to see.

jemigossaye

ASKER

thanks, it does retrun an object.