ConnectionStringsExpressionBuilder Class
Retrieves, or generates code to retrieve, values from the <connectionStrings> section of the Web.config file.
Assembly: System.Web (in System.Web.dll)
[AspNetHostingPermissionAttribute(SecurityAction::LinkDemand, Level = AspNetHostingPermissionLevel::Minimal)] [AspNetHostingPermissionAttribute(SecurityAction::InheritanceDemand, Level = AspNetHostingPermissionLevel::Minimal)] public ref class ConnectionStringsExpressionBuilder : public ExpressionBuilder
The ConnectionStringsExpressionBuilder class provides access to values in the <connectionStrings> section of the Web.config file. The <connectionStrings> section of the Web.config file contains connection string values in name/value pairs.
A connection string value is retrieved by assigning an expression of the form
<%$ ConnectionStrings: secureConnectionString %>
to a control property. The part of the expression before the colon (:) designates the type of expression to be retrieved, and the part after the colon signifies the name of the connection string. The preceding expression would retrieve the following value from the Web.config file.
<connectionStrings>
<add name="secureConnectionString" connectionString="Data
Source=localhost;Integrated Security=SSPI;Initial
Catalog=Northwind;" providerName="System.Data.SqlClient" />
</connectionStrings>
When the page parser encounters an expression with the prefix ConnectionStrings, it creates an instance of the ConnectionStringsExpressionBuilder class to handle the expression.
If the expression is encountered in a page that will be compiled, the ConnectionStringsExpressionBuilder object generates code that retrieves the specified connection string from the Web.config file. If the expression is encountered in a page that will not be compiled, the ConnectionStringsExpressionBuilder object returns the value from the Web.config file when the page is parsed.
The following code example demonstrates how to declaratively use a SqlDataSource control to retrieve data from a computer running Microsoft SQL Server and display it in a GridView control.
The code retrieves the following connection string from the Web.config file.
<configuration xmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0">
<connectionStrings>
<add name="MyNorthwind" connectionString="Data
Source=localhost;Integrated Security=SSPI;Initial
Catalog=Northwind;" providerName="System.Data.SqlClient" />
</connectionStrings>
</configuration>
- AspNetHostingPermission
for operating in a hosted environment. Demand value: LinkDemand; Permission value: Minimal.
- AspNetHostingPermission
for operating in a hosted environment. Demand value: InheritanceDemand; Permission value: Minimal.
System.Web.Compilation::ExpressionBuilder
System.Web.Compilation::ConnectionStringsExpressionBuilder
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.