ObjectQuery(Of T) Constructor (String, ObjectContext)

 

Creates a new ObjectQuery(Of T) instance using the specified Entity SQL command as the initial query.

Namespace:   System.Data.Objects
Assembly:  System.Data.Entity (in System.Data.Entity.dll)

Public Sub New (
	commandText As String,
	context As ObjectContext
)

Parameters

commandText
Type: System.String

The Entity SQL query.

context
Type: System.Data.Objects.ObjectContext

The ObjectContext on which to execute the query.

When your application generates Entity SQL queries at runtime, you should be aware of any command length limitations of the data source. Entity SQL does not enforce limitations on the length of the command text in queries.

The example in this topic is based on the AdventureWorks Sales Model. The example shows how to construct an instance of the ObjectQuery(Of T) class.

Using context As New AdventureWorksEntities()
    ' Call the constructor with a query for products and the ObjectContext. 
    Dim productQuery1 As New ObjectQuery(Of Product)("Products", context)

    For Each result As Product In productQuery1
        Console.WriteLine("Product Name: {0}", result.Name)
    Next

    Dim queryString As String = "SELECT VALUE product FROM AdventureWorksEntities.Products AS product"

    ' Call the constructor with the specified query and the ObjectContext. 
    Dim productQuery2 As New ObjectQuery(Of Product)(queryString, context)

    For Each result As Product In productQuery2
        Console.WriteLine("Product Name: {0}", result.Name)
    Next

    ' Call the constructor with the specified query, the ObjectContext, 
    ' and the NoTracking merge option. 
    Dim productQuery3 As New ObjectQuery(Of Product)(queryString, context, MergeOption.NoTracking)

    For Each result As Product In productQuery3
        Console.WriteLine("Product Name: {0}", result.Name)
    Next
End Using

.NET Framework
Available since 3.5
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