Hello Amitha,
you can create the connection string in web.config file.
for eg:
<appSettings>
<add key = "ConnectionString" value = "Persist Security Info=False; User ID=sa; Password=; Initial Catalog=NTBS; Data Source=(local)" />
</appSettings>


and you can call the connection string using
ConfigurationSettings.AppSettings["ConnectionString"];
command..

thanx for your reply sushanth,i have 1 more question for u,i developed one window aoolication using firbird database as stanalone server,so when i try to do any really fast on my running application(like click on datagrig values very contineously,than my application got hangs.and run again only when i restart my machine.can u help me this case also.................?

<appSettings/>
<connectionStrings>
<add name="pubsConnectionString1" connectionString="Data Source=P4C800E\SQLEXPRESS;Initial Catalog=pubs;Integrated Security=True"
providerName="System.Data.SqlClient" />
</connectionStrings>