Re: Invalid attempt to read when no data is present

From: Kevin Spencer (kevin_at_DIESPAMMERSDIEtakempis.com)
Date: 02/24/05 

Date: Thu, 24 Feb 2005 13:43:08 -0500

> string strSubject = Convert.ToString(dtrEmail["subject"]);
> string strContent = Convert.ToString(dtrEmail["content"]);

Are you checking for NULL values before attempting to convert them to
strings? A NULL cannot be converted to a string. Example:

string strSubject;
int ordinal;
ordinal = dtrEmail.GetOrdinal("subject");
if (!dtrEmail.IsDbNull(ordinal)
    strSubject = dtrEmail.GetString(ordinal);
else
    strSubject = ""; 

-- 
HTH,
Kevin Spencer
Microsoft MVP
.Net Developer
Neither a follower nor a lender be.
"Andy Sutorius" <andy@sutorius.com> wrote in message 
news:GCoTd.1391$ha.23643@twister.southeast.rr.com...
> Hi,
>
> I am getting the error "Invalid attempt to read when no data is present"
> when I run the following code. I have checked the sql and it is returning
> data. What am I missing?
>
>   string sqlGetEmail = "SELECT content, subject FROM tblContent WHERE id =
> " + Convert.ToInt16(ddlChooseEmail.SelectedValue.ToString());
>   SqlCommand cmdGetEmail = new SqlCommand(sqlGetEmail, strConnString);
>   SqlDataReader dtrEmail = cmdGetEmail.ExecuteReader();
>
>   string strSubject = Convert.ToString(dtrEmail["subject"]);
>   string strContent = Convert.ToString(dtrEmail["content"]);
>
>   dtrEmail.Close();
>
>
> Thanks,
>
> Andy
>
>

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