6

对于以下“项目”，我在解决 Unity for DI 时遇到了一个非常烦人且莫名其妙的错误。

InvalidOperationException - 无法构造类型 LogWriter。您必须配置容器以提供此值。

？例如消息；“依赖项解析失败，类型 = \"WindowsFormsApplication1.Performance\"，名称 = \"(none)\"。\r\n在解析时发生异常。\r\n异常是：InvalidOperationException - 类型 LogWriter 不能已构造。您必须配置容器以提供此值。\r\n--------------------------------- -------------\r\n出现异常时，容器为：\r\n\r\n Resolving WindowsFormsApplication1.Performance,(none)\r\n Resolving parameter \ "lw\" 的构造函数 WindowsFormsApplication1.Performance(Microsoft.Practices.EnterpriseLibrary.Logging.LogWriter lw, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.ExceptionManager em)\r\n 正在解决 Microsoft.Practices.EnterpriseLibrary.Logging.LogWriter,(none) \r\n"

?ex.StackTrace; " 在 Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable 1 resolverOverrides) in e:\\Builds\\Unity\\UnityTemp\\Compile\\Unity\\Unity\\Src\\UnityContainer.cs:line 515\r\n at Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, String name, IEnumerable1 resolverOverrides) 在 e:\Builds\Unity\UnityTemp\Compile\Unity\Unity\Src\UnityContainer.cs:line 485\ r\n 在 Microsoft.Practices.Unity.UnityContainer.Resolve(Type t, String name, ResolverOverride[] resolverOverrides) 在 e:\Builds\Unity\UnityTemp\Compile\Unity\Unity\Src\UnityContainer.cs:line 173\ r\n 在 Microsoft.Practices.Unity.UnityContainerExtensions.Resolve[T](IUnityContainer container, ResolverOverride[] overrides) 在 e:\Builds\Unity\UnityTemp\Compile\Unity\Unity\Src\UnityContainerExtensions.cs:line 504\ r\n 在 D:\Devzone\Tasking\WindowsFormsApplication1\Form1.cs:line 33 中的 WindowsFormsApplication1.Form1.OnLoad(EventArgs e)"

以一种形式：

  protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);

            try
            {
                IUnityContainer container = new UnityContainer();
                Performance p = container.Resolve<Performance>();
            }
            catch (Exception ex)
            {

            }
        }

依赖类：

 public class Performance
    {
        public Performance(LogWriter lw, ExceptionManager em)
        {
        }
    }

配置文件：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <configSections>
        <section name="loggingConfiguration" type="Microsoft.Practices.EnterpriseLibrary.Logging.Configuration.LoggingSettings, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
        <section name="exceptionHandling" type="Microsoft.Practices.EnterpriseLibrary.ExceptionHandling.Configuration.ExceptionHandlingSettings, Microsoft.Practices.EnterpriseLibrary.ExceptionHandling, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" requirePermission="true" />
    </configSections>
    <loggingConfiguration name="" tracingEnabled="true" defaultCategory="General">
        <listeners>
            <add name="Event Log Listener" type="Microsoft.Practices.EnterpriseLibrary.Logging.TraceListeners.FormattedEventLogTraceListener, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
                listenerDataType="Microsoft.Practices.EnterpriseLibrary.Logging.Configuration.FormattedEventLogTraceListenerData, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
                source="Enterprise Library Logging" formatter="Text Formatter"
                log="" machineName="." traceOutputOptions="None" />
        </listeners>
        <formatters>
            <add type="Microsoft.Practices.EnterpriseLibrary.Logging.Formatters.TextFormatter, Microsoft.Practices.EnterpriseLibrary.Logging, Version=5.0.414.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
                template="Timestamp: {timestamp}{newline}&#xA;Message: {message}{newline}&#xA;Category: {category}{newline}&#xA;Priority: {priority}{newline}&#xA;EventId: {eventid}{newline}&#xA;Severity: {severity}{newline}&#xA;Title:{title}{newline}&#xA;Machine: {localMachine}{newline}&#xA;App Domain: {localAppDomain}{newline}&#xA;ProcessId: {localProcessId}{newline}&#xA;Process Name: {localProcessName}{newline}&#xA;Thread Name: {threadName}{newline}&#xA;Win32 ThreadId:{win32ThreadId}{newline}&#xA;Extended Properties: {dictionary({key} - {value}{newline})}"
                name="Text Formatter" />
        </formatters>
        <categorySources>
            <add switchValue="All" name="General">
                <listeners>
                    <add name="Event Log Listener" />
                </listeners>
            </add>
            <add switchValue="All" name="Category2" />
        </categorySources>
        <specialSources>
            <allEvents switchValue="All" name="All Events" />
            <notProcessed switchValue="All" name="Unprocessed Category" />
            <errors switchValue="All" name="Logging Errors &amp; Warnings">
                <listeners>
                    <add name="Event Log Listener" />
                </listeners>
            </errors>
        </specialSources>
    </loggingConfiguration>
    <exceptionHandling>
        <exceptionPolicies>
            <add name="Policy">
                <exceptionTypes>
                    <add name="All Exceptions" type="System.Exception, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
                        postHandlingAction="NotifyRethrow" />
                </exceptionTypes>
            </add>
        </exceptionPolicies>
    </exceptionHandling>
</configuration>
4

5 回答 5

11

您需要将 Enterprise Library 扩展添加到您的容器中。没有它，容器就不会读取配置文件，因此不知道如何创建 Entlib 对象，例如 LogWriter。

于 2012-10-18T08:54:34.150 回答
1

尝试获取 LogWriter 类型的实例时发生激活错误，键“”

检查您的配置文件，它必须具有正确的默认“loggingConfiguration”部分

于 2015-10-27T12:22:22.663 回答
0

为了让 Unity 构造你的 Performance 类，它需要知道如何构造 ILogWriter 的实现。

我在您的代码中看不到您告诉 Unity 为 ILogWriter 接口创建什么类的任何地方，所以我怀疑您可能需要添加它。

于 2012-10-18T08:49:35.950 回答
0

LogWriter 没有空构造函数或具有所有具体类型参数的构造函数：LogWriter Constructor。

所以 Unity 无法构建它，正如它所说，它需要你的帮助，通过配置容器来提供实现。

作为确认， ExceptionManager 可能会被解决，因为它只有一个构造函数，也是无参数的:)

于 2012-10-18T08:51:04.187 回答
0

试试这个：

protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);

            try
            {
                IUnityContainer container = new UnityContainer();
                container.RegisterType<ILogWriter, LogWriter>();
                container.RegisterType<ExceptionManager>();
                container.RegisterType<Performance>(new InjectionConstructor(typeof(ILogWriter), typeof(ExceptionManager));                    
                Performance p = container.Resolve<Performance>();
            }
            catch (Exception ex)
            {

            }
        }
于 2012-10-18T08:53:56.620 回答