Using the ConnectionStrings element in ASP.NET web.configTags:
If you are building a series of web applications that
may rely on duplicate data (such as connection strings for pages that
query databases), or you want to separate certain constants from your
other code, you need a centralized method for storing and referencing
that data. In this case, the
ConnectionStrings element in the
web.config file of either your
application's root directory, parent directory, or the web server root
directory–depending on your application's inheritance–can prove
Keys can be created within the element and given values. These values can then be recalled by any web applications which inherit the settings from the particular web.config file. This can be a particularly advantageous tool for recycling database connection strings in web application suites and web service frameworks.
ASP.NET 2.0 (.NET Framework 3.5) web.config:
#!xml <?xml version="1.0" encoding="utf-8" ?> <configuration> <connectionStrings> <add name="databaseReader" connectionString="server=sqlserver.myhost.com;database=myDatabase;uid=username;pwd=password;" /> </connectionStrings> <system.web> <!– insert web-specific contents, et al –> </system.web> </configuration>
The example given above is a stripped-down implementation of web.config, and particular to database-driven web applications.
Now that you've got your data tucked away in the web.config file, it's time to use it
in your web application. We will make use of the
method in order to accomplish this:
VB.NET 3.5 code:
#!vbnet ' Grab the connection string from web.config's ConnectionStrings element Dim connStr as String = ConfigurationManager.ConnectionStrings("databaseReader").ConnectionString ' Connect to the database using the retrieved connection string Dim conn as SqlConnection = new SqlConnection(connStr) ' Output the database server's connection status Try conn.Open() Response.Write("Database connection was successful.<br />") Catch ex as Exception Response.Write("Could not connect to the database.<br />") End Try
Use this method in conjunction with the before-mentioned prepared
and you've got yourself a nifty little RDBMS connection that is
(somewhat) secure… and, more importantly, replicated even in the event
of a change to the
ConnectionStrings key's value.