记录：MOSS：EventHandler部署和使用

1.利用 Feature来实现 EventHandler与 SPList的绑定：

public class FeatureReceiver : SPFeatureReceiver {

public override void FeatureActivated(SPFeatureReceiverProperties properties)

{

try

{

using (SPSite site = new SPSite(((SPSite)properties.Feature.Parent).Url))

{

SPList list = site.RootWeb.Lists[TestListName.TestA];

// 将 list.EventReceiver.Class==ListEventHandler的事件删除

DeleteEventHandler(list, typeof(ListEventHandler));

// 重新添加：事件类型、事件程序集名、事件程序集下的事件类名

list.EventReceivers.Add(SPEventReceiverType.ItemAdded, typeof(FeatureReceiver).Assembly.FullName, typeof(TestEventHandler2.ListEventHandler).FullName);

list.EventReceivers.Add(SPEventReceiverType.ItemUpdated, typeof(FeatureReceiver).Assembly.FullName, typeof(TestEventHandler2.ListEventHandler).FullName);

list.EventReceivers.Add(SPEventReceiverType.ItemDeleting, typeof(FeatureReceiver).Assembly.FullName, typeof(TestEventHandler2.ListEventHandler).FullName);

}

}

catch (Exception ex)

{

}

}

public override void FeatureDeactivating(SPFeatureReceiverProperties properties) {

/* no op */

}

public override void FeatureInstalled(SPFeatureReceiverProperties properties) {

/* no op */

}

public override void FeatureUninstalling(SPFeatureReceiverProperties properties) {

/* no op */

}

/// <summary>

/// 删除指定SPList的事件句柄

/// </summary>

/// <param name="list">列表</param>

/// <param name="type">事件类的类型</param>

private void DeleteEventHandler(SPList list, Type type)

{

try

{

for (int i = list.EventReceivers.Count; i > 0; i--)

{

SPEventReceiverDefinition receiver = list.EventReceivers[i - 1];

if (receiver.Class.ToLower().Equals(type.FullName.ToLower()))

{

receiver.Delete();

}

}

}

catch (Exception ex)

{

}

}

}

2.事件操作：

public class ListEventHandler:SPItemEventReceiver

{

private static readonly string testA = TestListName.TestA;

private static readonly string testB = TestListName.TestB;

public override void ItemAdded(SPItemEventProperties properties)

{

base.ItemAdded(properties);

}

public override void ItemDeleting(SPItemEventProperties properties)

{

// Prevents events from being raised：阻止其他事件被调用

// 对应的是：EnableEventFiring()

this.DisableEventFiring();

int id = properties.ListItemId;

try

{

using (SPSite site = new SPSite(properties.SiteId))

{

using (SPWeb web = site.OpenWeb())

{

SPListCollection lists = web.Lists;

bool flag = web.AllowUnsafeUpdates;

web.AllowUnsafeUpdates = true;

for (int i = 0; i < lists.Count; i++)

{

if (lists[i].Title.Equals(testB))

{

SPList tempList = lists[i];

for (int j = 0; j < tempList.ItemCount; j++)

{

if (tempList.Items[j].ID.Equals(id))

{

tempList.Items[j].Delete();

tempList.Update();

}

}

}

}

web.AllowUnsafeUpdates = flag;

}

}

}

catch (Exception ex)

{

}

finally

{

}

}

public override void ItemUpdated(SPItemEventProperties properties)

{

base.ItemUpdated(properties);

}

}

常用的EventHandler事件有：

ItemAdding：添加前；

ItemAdded：添加后；

ItemUpdating：更新前；

ItemUpdated：更新后；

ItemDeleting：删除前；

ItemDeleted：删除后；

最常用的是：ItemAdded、ItemUpdating、ItemDeleting；

this.DisableEventFiring();是为了避免调用ItemEventReceiver事件。

可以参照以下资料：http://www.nanmu.net/keli/blog/Lists/Posts/Post.aspx?ID=38

(1).在开发SharePoint的EventHandler也许你会有这样的需求：在ItemUpdated事件中修改当前记录的某个字段的值，这样在修改的时候又会触发ItemUpdated事件，为了避免在此触发ItemUpdated事件，可以用this.DisableEventFiring()方法；

try

{

this.DisableEventFiring();

...

...

Item.Update();

}

finally

{

this.EnableEventFiring();

}

注：

也可以使用 SPItem.SystemUpdate()方法来更改，这样也不会触发ItemUpdated事件；

(2).在 SPItemEventReceiver.ItemUpdating, ItemAdding events:

properties.AfterProperties["Title"] = "the Title changed at " + DateTime.Now.ToString();

这样就可以更改SPItem.Title的内容，且不会触发任何的 ItemEventReceiver事件。