ASP.NET 2.0 brought a new feature called Expression Builder, which allows you to assign dynamic values to a control’s property. The syntax is very similar to the well known <%= value %> and <%# bind(“property”) %>: <%$ expression %>
Please note the “$”. This syntax can be found mostly for connection strings when doing some declarative binding with ASP.NET:
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:MyConnectionString %>" />
This built in Expression uses the connection string MyConnectionString found in the Web.Config.
It is a fact that with Azure it is better to store the AppSettings and Connection Strings in the CSCFG...