LinqDataSourceSelectEventArgs Class
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LinqDataSourceSelectEventArgs Class

 

Provides data for the Selecting event.

Namespace:   System.Web.UI.WebControls
Assembly:  System.Web.Extensions (in System.Web.Extensions.dll)

System.Object
  System.EventArgs
    System.ComponentModel.CancelEventArgs
      System.Web.UI.WebControls.LinqDataSourceSelectEventArgs

public class LinqDataSourceSelectEventArgs : CancelEventArgs

NameDescription
System_CAPS_pubpropertyArguments

Gets values that determine how the data is returned.

System_CAPS_pubpropertyCancel

Gets or sets a value indicating whether the event should be canceled.(Inherited from CancelEventArgs.)

System_CAPS_pubpropertyGroupByParameters

Gets the collection of parameters that is used to create the GroupBy clause.

System_CAPS_pubpropertyOrderByParameters

Gets the collection of parameters that is used to create the OrderBy clause.

System_CAPS_pubpropertyOrderGroupsByParameters

Gets the collection of parameters that are used to create the clause that specifies how grouped data is sorted.

System_CAPS_pubpropertyResult

Gets or sets the data object that is used in the data query.

System_CAPS_pubpropertySelectParameters

Gets the collection of parameters that is used to create the Select clause.

System_CAPS_pubpropertyWhereParameters

Gets the collection of parameters that is used to create the Where clause.

NameDescription
System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

The LinqDataSourceSelectEventArgs object is passed to event handlers for the Selecting event of the LinqDataSource control. You use the LinqDataSourceSelectEventArgs object to manually specify what data is returned, and how the data is sorted and paged when it is returned. You can programmatically add or remove parameters to the GroupBy, OrderBy, OrderGroupsBy, Select, and Where clauses by using the GroupByParameters, OrderByParameters, OrderGroupsByParameters, SelectParameters, and WhereParameters collections.

The Result property enables you to change the data object that is used for the query. If you assign an object to the Result property, that object will be used for queries instead of the object specified in the TableName property of the LinqDataSource control.

The Arguments property enables you to customize how returned data is sorted and paged. The data-bound control passes sorting and paging properties through the Arguments property. If you have to manually handle sorting or paging, set the AutoSort property or AutoPage property of the LinqDataSource control to false. You can then perform the customized query for sorting or paging in a handler for the Selecting event.

If the RetrieveTotalRowCount property is set to true, you must return a value for the TotalRowCount property.

The following example shows how to set the Result property to the result of a search made by using language-integrated query (LINQ).

protected void LinqDataSource_Selecting(object sender, LinqDataSourceSelectEventArgs e)
{
    ExampleDataContext exampleContext = new ExampleDataContext();

    e.Result = from p in exampleContext.Products 
         where p.Category == "Beverages"
         select new {
           ID = p.ProductID,
           Name = p.Name
         };
}

The following example shows how to set the Result property to an array of string values that is defined in the Web page.

public partial class Default3 : System.Web.UI.Page
{
    string[] citiesArray = 
    { 
        "Atlanta", 
        "Charlotte", 
        "Denver", 
        "New York", 
        "San Francisco" 
    };

    protected void Page_Load(object sender, EventArgs e)
    {
    }

    protected void LinqDataSource_Selecting(object sender, LinqDataSourceSelectEventArgs e)
    {
        var cities = from city in citiesArray
                     where city.CompareTo("B") > 0
                     select city;
        e.Result = cities;
        // Or we could set e.Result = citiesArray to return all rows.
    }
}

.NET Framework
Available since 3.5

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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