EntityDataSource::WhereParameters Property
Gets the collection of parameters that are used to create the WHERE clause.
Assembly: System.Web.Entity (in System.Web.Entity.dll)
[PersistenceModeAttribute(PersistenceMode::InnerProperty)] [BrowsableAttribute(false)] public: virtual property ParameterCollection^ WhereParameters { ParameterCollection^ get () sealed; }
Property Value
Type: System.Web.UI.WebControls::ParameterCollectionThe parameters that are used for creating the WHERE clause.
Implements
IDynamicDataSource::WhereParametersLike the Where method of the ObjectQuery<T> class, parameters can be passed to the predicate assigned to the Where property. The WhereParameters property of the EntityDataSource control specifies a ParameterCollection that contains the parameters to supply to the WHERE clause of the query. The WhereParameters property uses named arguments to refer to the parameters that are specified in the string that is supplied to the Where property.
If the WhereParameters property is not set, no parameter substitution is made. All the parameter names in the WHERE clause preceded by the symbol "@" must have a matching name in the ParameterCollection. Null values are not allowed for parameters in a ParameterCollection.
The XML markup in the following example, in an .aspx file, retrieves a value from a control and passes it as a parameter to the Where property.
<asp:EntityDataSource ID="SalesOrderHeader" runat="server"
ConnectionString="name=AdventureWorksEntities"
DefaultContainerName="AdventureWorksEntities" EnableDelete="True"
EnableInsert="True" EnableUpdate="True" EntitySetName="SalesOrderHeader"
EntityTypeFilter="" OrderBy="it.TotalDue DESC" Select=""
Where="it.OnlineOrderFlag = TRUE AND it.TotalDue > @ordercost">
<WhereParameters>
<asp:ControlParameter ControlID="costLimit" DbType="Int32"
DefaultValue="2500" Name="ordercost" PropertyName="Text" />
</WhereParameters>
</asp:EntityDataSource>
The previous XML example is the same as the following ObjectQuery<T> named onlineOrders:
ObjectQuery<SalesOrderHeader> onlineOrders =
context.SalesOrderHeader
.Where("it.OnlineOrderFlag = TRUE AND it.TotalDue > @ordercost",
new ObjectParameter("ordercost", orderCost))
.OrderBy("it.TotalDue DESC");
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
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.