Using Connection Strings from Web.config in ASP.NET v2.0
By Scott Forsyth
August 26, 2005
ASP.NET v2.0 has a couple new ways to reference connection strings stored in the
web.config or machine.config file.
A typical web.config file in v2.0 could have the following
section which is placed directly under the root <configuration> section:
<connectionstrings>
<remove name="LocalSqlServer">
<add name="LocalSqlServer"
connectionString="data source=.\SQLEXPRESS;Integrated
Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient"/>
<add name="MainConnStr"
connectionString="data source=.\SQLEXPRESS;Integrated
Security=SSPI;AttachDBFilename=|DataDirectory|main.mdf;User Instance=true" providerName="System.Data.SqlClient">
</connectionStrings>
connectionStrings>
<remove
name="LocalSqlServer">
<add name="LocalSqlServer"
connectionString="data source=.\SQLEXPRESS;Integrated
Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true" providerName="System.Data.SqlClient"/>
<add name="MainConnStr"
connectionString="data source=.\SQLEXPRESS;Integrated
Security=SSPI;AttachDBFilename=|DataDirectory|main.mdf;User Instance=true" providerName="System.Data.SqlClient"/>
</connectionStrings>
You can reference this directly from code using:
[C#] string connStr = ConfigurationManager.ConnectionStrings["MainConnStr"].ConnectionString;
[VB] Dim connStr
As String = ConfigurationManager.ConnectionStrings("MainConnStr").ConnectionString
Note that the namespace for this is System.Configuration so for a console application
the full namespace is required.
Or you can reference this declaratively within the ConnectionString property of
a SqlDataSource:
<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:MainConnStr %>"
SelectCommand="SELECT [au_id], [au_lname], [au_fname], [state] FROM [authors]"/>
Scott Forsyth is the Director of IT at
ORCS Web, Inc.
- a company that provides managed hosting solutions for clients who develop and deploy their applications on Microsoft Windows platforms. Services include shared hosting, dedicated hosting, and webfarm hosting, with specialty in .Net, SQL Server, and architecting highly scalable solutions.