RangeExpression Class

Reference

Definition

Namespace:: System.Web.UI.WebControls.Expressions

Assembly:: System.Web.Extensions.dll

Important

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Provides a way to determine whether a value is greater than or less than a specified value, or whether a value is between two specified values.

public ref class RangeExpression : System::Web::UI::WebControls::Expressions::ParameterDataSourceExpression

public class RangeExpression : System.Web.UI.WebControls.Expressions.ParameterDataSourceExpression

type RangeExpression = class
    inherit ParameterDataSourceExpression

Public Class RangeExpression
Inherits ParameterDataSourceExpression

Inheritance: Object

DataSourceExpression

ParameterDataSourceExpression
RangeExpression

Examples

The following example shows how to search the ListPrice column in the Products table of the AdventureWorks database for products that have a list price in the range that is specified in the FromTextBox and ToTextBox text boxes. The filter includes the minimum value but excludes the maximum value in the results. The results are displayed in a Label control.

This code example is part of a larger example provided in Walkthrough: Filtering Data in a Web Page Using Declarative Syntax.

Remarks

The QueryExtender control provides the ability to filter data in a Web page by using classes in the System.Web.UI.WebControls.Expressions namespace. These classes include the RangeExpression class.

The RangeExpression class searches a data column using a pair of values that define the range. You use the DataField property to specify the column to search. You use the MinType property to specify whether to include or exclude the minimum in the search results, and you use the MaxType property to specify whether to include or exclude the maximum value. The maximum and minimum values can be specified in ASP.NET controls and the values can then be passed to the QueryExtender control as parameters in ControlParameter controls. The results are typically displayed in a data-bound control.

Constructors

RangeExpression()

Initializes a new instance of the RangeExpression class.

Properties

Context	Gets the HttpContext instance of the owner control. (Inherited from DataSourceExpression)
DataField	Gets or sets the field to use for the comparison.
DataSource	Gets the data source object that is associated with the owner control. (Inherited from DataSourceExpression)
IsTrackingViewState	Gets a value that indicates whether a data source expression object is tracking its view state changes. (Inherited from DataSourceExpression)
MaxType	Gets or sets the maximum value of the range.
MinType	Gets or sets the minimum value of the range.
Owner	Gets the owner control. (Inherited from DataSourceExpression)
Parameters	Gets the parameters that are associated with this DataSourceExpression object. (Inherited from ParameterDataSourceExpression)
ViewState	Gets an instance of the StateBag class that contains the current view state information. (Inherited from DataSourceExpression)

Methods

Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetQueryable(IQueryable)	Gets the IQueryable object that the range comparison was performed on.
GetType()	Gets the Type of the current instance. (Inherited from Object)
LoadViewState(Object)	Loads the state of the values in the ParameterDataSourceExpression object that must be persisted. (Inherited from ParameterDataSourceExpression)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
SaveViewState()	Saves the current view state of the ParameterDataSourceExpression object. (Inherited from ParameterDataSourceExpression)
SetContext(Control, HttpContext, IQueryableDataSource)	Executes the expression by using the specified owner control, context, and data source. (Inherited from ParameterDataSourceExpression)
SetDirty()	Marks the DataSourceExpression object so that its state will be saved in view state. (Inherited from DataSourceExpression)
ToString()	Returns a string that represents the current object. (Inherited from Object)
TrackViewState()	Tracks view-state changes of the ParameterDataSourceExpression object so that the changes can be stored in the StateBag object for the object. (Inherited from ParameterDataSourceExpression)

Explicit Interface Implementations

IStateManager.IsTrackingViewState	When implemented by a class, gets a value that indicates whether a data source expression object is tracking its view state changes. (Inherited from DataSourceExpression)
IStateManager.LoadViewState(Object)	When implemented by a class, loads the previously saved view state of the data source expression object. (Inherited from DataSourceExpression)
IStateManager.SaveViewState()	When implemented by a class, saves the current view state of the DataSourceExpression object. (Inherited from DataSourceExpression)
IStateManager.TrackViewState()	When implemented by a class, tracks view state changes of the DataSourceExpression object so that the changes can be stored in the StateBag object for the data source expression object. (Inherited from DataSourceExpression)

Applies to

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