The ConnectionString property has not been initialized.

Bit late I know but,

There is a similar section in the app/web.config specifically for connectionStrings:

<connectionstrings>
<add name="MyConnectionString">
connectionString="Data Source=SQLServer\Instance;Initial Catalog=MyDatabaseName;User ID=sqlServerUser;Password=Password"
providerName="System.Data.SqlClient" />


this goes into the <configuration> section of the config. Sql, authentication is optional - substitute your connection string if required to use windows authentication via Integrated Security=True.

then:

change the code you've written to:

SqlConnection conn = new SqlConnection();
conn.ConnectionString = ConfigurationManager.ConnectionString["MyConnectionString"].ConnectionString;

conn.Open();

The benefit of using this section is it is clear to other developers what the purpose of this string is, which is obviously as a connection string.

hai,
first u debug your program by using breakpoints.........
then i preferred u to build your database connection through Datasets.............
I think it is easily accessible & simple in programming...........
Best of luck................
bye.........
Thnks......

string constr = ConfigurationManager.ConnectionStrings["getconn"].ToString();
SqlConnection con = new SqlConnection(constr);
con.Open();