Class ContinuousQuery

Class to hold Object query and values, intended for notifications.

Inheritance

System.Object

ContinuousQuery

Namespace:

Assembly: Alachisoft.NCache.Web.dll

Syntax

public class ContinuousQuery

ContinuousQuery(String, Hashtable)

Initializes a new instance of the ContinuousQuery class.

Declaration

public ContinuousQuery(string query, Hashtable values)

Parameters

Type	Name	Description
System.String	query	Query text
System.Collections.Hashtable	values	Query values

CQREFSTARTAdd

Declaration

public const short CQREFSTARTAdd = 2000

Field Value

Type	Description
System.Int16

CQREFSTARTRemove

Declaration

public const short CQREFSTARTRemove = 3000

Field Value

Type	Description
System.Int16

CQREFSTARTUpdate

Declaration

public const short CQREFSTARTUpdate = 4000

Field Value

Type	Description
System.Int16

Query

Query text.

Declaration

public string Query { get; set; }

Property Value

Type	Description
System.String

Values

Query values.

Declaration

public Hashtable Values { get; set; }

Property Value

Type	Description
System.Collections.Hashtable

Equals(Object)

Compares two instances of ContinuousQuery for equality.

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
System.Object	obj

Returns

Type	Description
System.Boolean	true if both ContinuousQuery instances are the same. Otherwise false.

Overrides

System.Object.Equals(System.Object)

GetHashCode()

Compoutes the hash code for the current object.

Declaration

public override int GetHashCode()

Returns

Type	Description
System.Int32	Hash code for the current object

Overrides

System.Object.GetHashCode()

RegisterAddNotification(ContinuousQueryItemAddedCallback)

Registers notification for item added in ContinuousQuery resultset.

Declaration

[Obsolete("Use RegisterCQ(QueryDataNotificationCallback callback,EventType eventType,EventDataFilter datafilter")]
public void RegisterAddNotification(ContinuousQueryItemAddedCallback itemAddedCallback)

Parameters

Type	Name	Description
ContinuousQueryItemAddedCallback	itemAddedCallback

RegisterClearNotification(ContinuousQueryClearCallback)

This method registers a custom callback that is fired if dataset of a continous query is cleared

Declaration

public void RegisterClearNotification(ContinuousQueryClearCallback callback)

Parameters

Type	Name	Description
ContinuousQueryClearCallback	callback	A delegate to register your custom method with

Examples

/// First create an CacheClearedCallback

 public static void CacheCleared()
  {
    ...
  }

Then declare your continous query

ContinuousQuery cQ=new ContinuousQuery(query,Hashtable vals);

Then register your notification callback

cQ.RegisterClearNotification(new ContinuousQueryClearCallback(CacheCleared));

RegisterNotification(QueryDataNotificationCallback, EventType, EventDataFilter)

This method registers a custom callback that is fired on change in dataset of a continous query

Declaration

public void RegisterNotification(QueryDataNotificationCallback callback, EventType eventType, EventDataFilter datafilter)

Parameters

Type	Name	Description
QueryDataNotificationCallback	callback	A delegate to register your custom method with
Alachisoft.NCache.Runtime.Events.EventType	eventType	Describes whether the event is to be raised on Item Added, Updated or Removed
Alachisoft.NCache.Runtime.Events.EventDataFilter	datafilter	This enum is to describe when registering an event, upon raise how much data is retrieved from cache when the event is raised

Examples

/// First create an ItemCallback

ItemCallback(string key, CacheEventArg e)
{
   ...
}

Then declare your continous query

ContinuousQuery cQ=new ContinuousQuery(query,Hashtable vals);

Then register your notification callback

cQ.RegisterNotification(new QueryDataNotificationCallback(ItemCallback),EventType.ItemAdded, EventDataFilter.None);

RegisterRemoveNotification(ContinuousQueryItemRemovedCallback)

Registers notification for item removed from ContinuousQuery resultset.

Declaration

[Obsolete("Use RegisterCQ(QueryDataNotificationCallback callback,EventType eventType,EventDataFilter datafilter")]
public void RegisterRemoveNotification(ContinuousQueryItemRemovedCallback itemRemovedCallback)

Parameters

Type	Name	Description
ContinuousQueryItemRemovedCallback	itemRemovedCallback

RegisterUpdateNotification(ContinuousQueryItemUpdatedCallback)

Registers notification for item updated in ContinuousQuery resultset.

Declaration

[Obsolete("Use RegisterNotification(QueryDataNotificationCallback callback,EventType eventType,EventDataFilter datafilter")]
public void RegisterUpdateNotification(ContinuousQueryItemUpdatedCallback itemUpdatedCallback)

Parameters

Type	Name	Description
ContinuousQueryItemUpdatedCallback	itemUpdatedCallback

UnRegisterClearNotification(ContinuousQueryClearCallback)

This method Unregisters the clear callback

Declaration

public void UnRegisterClearNotification(ContinuousQueryClearCallback callback)

Parameters

Type	Name	Description
ContinuousQueryClearCallback	callback	A delegate to register your custom method with

Examples

Lets consider we registered a ClearNotification

 public static void CacheCleared()
  {
    ...
  }

Then unregister your notification callback

cQ.UnRegisterClearNotification(new ContinuousQueryClearCallback(CacheCleared));

UnRegisterNotification(QueryDataNotificationCallback, EventType)

This method Unregisters a custom callback that is fired on change in dataset of a continous query

Declaration

public void UnRegisterNotification(QueryDataNotificationCallback callback, EventType eventType)

Parameters

Type	Name	Description
QueryDataNotificationCallback	callback	A delegate to register your custom method with
Alachisoft.NCache.Runtime.Events.EventType	eventType	Describes whether the event is to be raised on Item Added, Updated or Removed

Examples

Lets consider we created an ItemCallback

ItemCallback(string key, CacheEventArg e)
{
   ...
}

Uregister your notification callback

cQ.RegisterNotification(new QueryDataNotificationCallback(ItemCallback),EventType.ItemAdded);