事件触发时显示警报消息

Question

我有以下要求.我已经存储了一个字典项列表.我希望Dictionary Key是唯一的.我编写了以下代码,就像任何新项目使用现有密钥名称保存一样,它应该抛出类似"项已存在"的警报.

我正在做的是在保存项目时将Key值与现有字典键进行比较.我已经在ItemSaving事件中编写了代码.

 public class IsItemExist
    {
        Sitecore.Data.Database master = Sitecore.Configuration.Factory.GetDatabase("master");

        public void OnItemSaving(object sender, EventArgs args)
        {

            Item dbItem = master.GetItem("/sitecore/content/Administration/Development Settings/Lookups");
            Item selectedItem = Event.ExtractParameter(args, 0) as Item;
            foreach (Item item in dbItem.Axes.GetDescendants())
            {
                if (item.Template.Name.Contains("entry"))
                {
                    if (item.Fields["Key"].Value == selectedItem.Fields["Key"].Value)
                    {
                        Sitecore.Context.ClientPage.ClientResponse.Alert("Item is already exist");
                    }
                }
            }

        }


    }

web.config条目

<event name="item:saving">
<handler type="CustomEvent.IsItemExist, CustomEvent" method="OnItemSaving"/>
</event>

它显示警报消息,我可以保存该项目.1.我不想再次使用重复值保存项目.点击保存按钮后,我得到2个警报信息.为什么？

任何帮助将不胜感激.谢谢各位...

Answer 1

您应该将处理程序添加到item:adding事件并将Cancel事件结果的属性设置为true:

  <event name="item:adding">
    <handler type="CustomEvent.DoesItemExist, CustomEvent" method="OnItemAdding" />
  </event>

public class DoesItemExist
{
    Sitecore.Data.Database master = Sitecore.Configuration.Factory.GetDatabase("master");

    public void OnItemAdding(object sender, EventArgs args)
    {
        Item dbItem = master.GetItem("/sitecore/content/Administration/Development Settings/Lookups");
        Item selectedItem = Event.ExtractParameter(args, 0) as Item;
        foreach (Item item in dbItem.Axes.GetDescendants())
        {
            if (item.Template.Name.Contains("entry"))
            {
                if (item.Fields["Key"].Value == selectedItem.Fields["Key"].Value)
                {
                    SitecoreEventArgs evt = args as SitecoreEventArgs;
                    evt.Result.Cancel = true;
                    Sitecore.Context.ClientPage.ClientResponse.Alert("Item already exists");
                }
            }
        }
    }
}