MEF生命周期

MEF生命周期
MEF生命周期分为三种:
ANY:MEF根据自己的需要设置是否共享
Shared:共享部件,可以在多个MEF组合容器中使用
NoShared:不共享部件,每次使用都需要创建实例
在MEF的实现通过PartCreationPolicyAttribute特性实现对部件的生命周期配置。
使用举例:
///导出
using System.ComponentModel.Composition;

namespace MEF0001
{
public interface IMetadata
{
string Name { get; }
}
public interface ILog
{
string Write();
}
[PartCreationPolicy(CreationPolicy.Any)]
[ExportMetadata("Name", "DBLOG")]
[Export(typeof(ILog))]
public class DBLog : ILog
{
public string Write()
{
return "DBLOG";
}
}
[PartCreationPolicy(CreationPolicy.Shared)]
[ExportMetadata("Name", "TXTLOG")]
[Export(typeof(ILog))]
public class TXTLog : ILog
{
public string Write()
{
return "TXTLog";
}
}
[PartCreationPolicy(CreationPolicy.NonShared)]
[ExportMetadata("Name", "XMLLOG")]
[Export(typeof(ILog))]
public class XMLLog : ILog
{
public string Write()
{
return "XMLLog";
}
}
}
///导入
#region 元数据导入 和 MEF生命周期
[ImportMany(typeof(ILog),RequiredCreationPolicy=CreationPolicy.NonShared)]
public Lazy[] Logs { get; set; }
public string Run()
{
string value = https://www.it610.com/article/string.Empty;
foreach (var log in Logs)
{
value += log.Metadata.Name + "\n";
}
return value;
}

#endregion

示例代码(该示例代码包括延迟加载和元数据加载及MEF生命周期):http://files.cnblogs.com/Clivia/MEF001.rar
【MEF生命周期】转载于:https://www.cnblogs.com/Clivia/archive/2010/11/12/MEF11.html

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