WCF 常见逻辑和代码 2.参数检查 BeforeCall And AfterCall

这段代码可以直接在wcf4.0中跑...需要的人就拷贝走吧...

我经常也会忘记代码..做个备份

虽然.net已经内置了一些类型用于检查输入参数 例如DataLengthAttribute

不过毕竟功能有限,实现自己的参数检查会更强大点.

有些东西是内置无法实现的, 例如在输入的时候检查权限,Request还有记录运行时间等

以下是C#代码(这里只是一种实现, IParameterInspector 还可以被应用到其他的地方 例如面对EndPoint和Attribute)

    public class ValidationBehaviorSection : BehaviorExtensionElement, IServiceBehavior
    {

        private const string EnabledAttributeName = "enabled";

        [ConfigurationProperty(EnabledAttributeName, DefaultValue = true, IsRequired = false)]
        public bool Enabled
        {
            get { return (bool)base[EnabledAttributeName]; }
            set { base[EnabledAttributeName] = value; }
        }

        protected override object CreateBehavior()
        {
            return this;
        }

        public override Type BehaviorType
        {
            get
            {
                return GetType();
            }
        }
        private ValidationParameterInspector GetInstance()
        {
            return new ValidationParameterInspector();
        }

        void IServiceBehavior.AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
        {
        }

        void IServiceBehavior.ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
        {
            if (!Enabled)
            {
                return;
            }
            ValidationParameterInspector inspector = GetInstance();
            foreach (ChannelDispatcher chDisp in serviceHostBase.ChannelDispatchers)
            {
                foreach (EndpointDispatcher epDisp in chDisp.Endpoints)
                {
                    // epDisp.DispatchRuntime.MessageInspectors.Add(new ValidationParameterInspector());
                    foreach (DispatchOperation op in epDisp.DispatchRuntime.Operations)
                        op.ParameterInspectors.Add(inspector);
                }
            }
        }

        void IServiceBehavior.Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase)
        {

        }
    }
 
    public class ValidationParameterInspector : IParameterInspector
    {
        private DateTime startTime;
        public void AfterCall(string operationName, object[] outputs, object returnValue, object correlationState)
        {

        }

        public object BeforeCall(string operationName, object[] inputs)
        {
            startTime = DateTime.Now;
            return null;
        }
    }

下面是web.confg的配置

    <extensions>
      <behaviorExtensions>
        <add name="validator" type="{命名空间}.ValidationBehaviorSection, {dll名字}"/>
      </behaviorExtensions>
    </extensions>
    <behaviors>
      <serviceBehaviors>
        <behavior>
          <validator />
        </behavior>
      </serviceBehaviors>
    </behaviors>