IObjectSpace.CreateDataView(Type, String, CriteriaOperator, IList<SortProperty>) Method

Returns a list of data records retrieved from a database without loading complete business classes (a data view). Values in each data record can be obtained from specific business class properties directly, or be evaluated by the database server using complex expressions.

Namespace: DevExpress.ExpressApp

Assembly: DevExpress.ExpressApp.v23.2.dll

NuGet Package: DevExpress.ExpressApp

Declaration

C#

IList CreateDataView(
    Type objectType,
    string expressions,
    CriteriaOperator criteria,
    IList<SortProperty> sorting
)

VB.NET

Function CreateDataView(
    objectType As Type,
    expressions As String,
    criteria As CriteriaOperator,
    sorting As IList(Of SortProperty)
) As IList

Parameters

Name	Type	Description
objectType	Type	The Type of requested objects.
expressions	String	A string that contains a semicolon separated list of expressions that specify data view column values.
criteria	CriteriaOperator	A CriteriaOperator object that specifies criteria associated with the data view.
sorting	IList<SortProperty>	An IList<SortProperty> collection whose elements identify the sorted columns within the data view.

Returns

Type	Description
IList	An IList object that returns a lightweight list of data records.

Remarks

This method does not return real objects. Instead, a lightweight read-only list of data records that can be viewed much more quickly than a real objects collection is returned.

This method result can be directly cast to XafDataView.

Note

If the passed property name conflicts with a function name, wrap the name in square brackets (e.g. “Oid;[Count];Price”). If you subsequently need to access such a property via a data record, you do not need to use brackets.

C#

XafDataView dataView = (XafDataView)objectSpace.CreateDataView(
    typeof(Product), "ID;Name;Sales.Sum([Count] * Price)", null, null);

VB.NET

Dim dataView As XafDataView = CType(objectSpace.CreateDataView( _
    GetType(Product), "ID;Name;Sales.Sum([Count] * Price)", Nothing, Nothing), XafDataView)