C# Config.InstallationContext类代码示例

        static int Main(string[] args)
        {
            try
            {
                using (var context = new InstallationContext())
                {
                    context.LogOutput = Console.Out;

                    XmlLoggingConfiguration configuration = null;

                    bool uninstallMode = false;

                    for (int i = 0; i < args.Length; ++i)
                    {
                        switch (args[i])
                        {
                            case "-q":
                                context.LogOutput = TextWriter.Null;
                                break;

                            case "-consolelog":
                                context.LogOutput = Console.Out;
                                break;

                            case "-loglevel":
                                context.LogLevel = LogLevel.FromString(args[++i]);
                                break;

                            case "-i":
                                context.IgnoreFailures = true;
                                break;

                            case "-log":
                                context.LogOutput = File.CreateText(args[++i]);
                                break;

                            case "-p":
                                string arg = args[++i];
                                int p = arg.IndexOf('=');
                                if (p < 0)
                                {
                                    Console.WriteLine("Parameter '{0}' must be NAME=VALUE", arg);
                                    Usage();
                                    return 1;
                                }

                                string paramName = arg.Substring(0, p);
                                string paramValue = arg.Substring(p + 1);
                                context.Parameters.Add(paramName, paramValue);
                                break;

                            case "-u":
                                uninstallMode = true;
                                break;

                            case "-?":
                                Usage();
                                return 0;

                            default:
                                if (args[i].StartsWith("-"))
                                {
                                    Usage();
                                    return 1;
                                }

                                configuration = new XmlLoggingConfiguration(args[i]);
                                break;
                        }
                    }

                    if (configuration == null)
                    {
                        Usage();
                        return 1;
                    }

                    if (uninstallMode)
                    {
                        configuration.Uninstall(context);
                    }
                    else
                    {
                        configuration.Install(context);
                    }

                    return 0;
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("EXCEPTION: {0}", ex);
                return 1;
            }
        }

 /// <summary>
 /// Performs uninstallation which requires administrative permissions.
 /// </summary>
 /// <param name="installationContext">The installation context.</param>
 public void Uninstall(InstallationContext installationContext)
 {
     EventLog.DeleteEventSource(this.Source, this.MachineName);
 }

 /// <summary>
 /// Determines whether the item is installed.
 /// </summary>
 /// <param name="installationContext">The installation context.</param>
 /// <returns>
 /// Value indicating whether the item is installed or null if it is not possible to determine.
 /// </returns>
 public bool? IsInstalled(InstallationContext installationContext)
 {
     return EventLog.SourceExists(this.Source, this.MachineName);
 }

        /// <summary>
        /// Ensures that the performance counter has been initialized.
        /// </summary>
        /// <returns>True if the performance counter is operational, false otherwise.</returns>
        private bool EnsureInitialized()
        {
            if (!this.initialized)
            {
                this.initialized = true;

                if (this.AutoCreate)
                {
                    using (var context = new InstallationContext())
                    {
                        this.Install(context);
                    }
                }

                try
                {
                    this.perfCounter = new PerformanceCounter(this.CategoryName, this.CounterName, this.InstanceName, false);
                }
                catch (Exception exception)
                {
                    if (exception.MustBeRethrown())
                    {
                        throw;
                    }

                    InternalLogger.Error("Cannot open performance counter {0}/{1}/{2}: {3}", this.CategoryName, this.CounterName, this.InstanceName, exception);
                }
            }

            return this.perfCounter != null;
        }

        /// <summary>
        /// Performs installation which requires administrative permissions.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        public void Install(InstallationContext installationContext)
        {
            if (EventLog.SourceExists(this.Source, this.MachineName))
            {
                string currentLogName = EventLog.LogNameFromSourceName(this.Source, this.MachineName);
                if (currentLogName != this.Log)
                {
                    // re-create the association between Log and Source
                    EventLog.DeleteEventSource(this.Source, this.MachineName);

                    var escd = new EventSourceCreationData(this.Source, this.Log)
                    {
                        MachineName = this.MachineName
                    };

                    EventLog.CreateEventSource(escd);
                }
            }
            else
            {
                var escd = new EventSourceCreationData(this.Source, this.Log)
                {
                    MachineName = this.MachineName
                };

                EventLog.CreateEventSource(escd);
            }
        }

        /// <summary>
        /// Determines whether the item is installed.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        /// <returns>
        /// Value indicating whether the item is installed or null if it is not possible to determine.
        /// </returns>
        public bool? IsInstalled(InstallationContext installationContext)
        {
            if (!PerformanceCounterCategory.Exists(this.CategoryName))
            {
                return false;
            }

            return PerformanceCounterCategory.CounterExists(this.CounterName, this.CategoryName);
        }

        /// <summary>
        /// Performs uninstallation which requires administrative permissions.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        public void Uninstall(InstallationContext installationContext)
        {
            string categoryName = this.CategoryName;

            if (PerformanceCounterCategory.Exists(categoryName))
            {
                installationContext.Debug("Deleting category '{0}'", categoryName);
                PerformanceCounterCategory.Delete(categoryName);
            }
            else
            {
                installationContext.Debug("Category '{0}' does not exist.", categoryName);
            }
        }

        private void RunInstallCommands(InstallationContext installationContext, IEnumerable<DatabaseCommandInfo> commands)
        {
            // create log event that will be used to render all layouts
            LogEventInfo logEvent = installationContext.CreateLogEvent();

            try
            {
                foreach (var commandInfo in commands)
                {
                    string cs;

                    if (commandInfo.ConnectionString != null)
                    {
                        // if there is connection string specified on the command info, use it
                        cs = commandInfo.ConnectionString.Render(logEvent);
                    }
                    else if (this.InstallConnectionString != null)
                    {
                        // next, try InstallConnectionString
                        cs = this.InstallConnectionString.Render(logEvent);
                    }
                    else
                    {
                        // if it's not defined, fall back to regular connection string
                        cs = this.BuildConnectionString(logEvent);
                    }

                    this.EnsureConnectionOpen(cs);

                    var command = this.activeConnection.CreateCommand();
                    command.CommandType = commandInfo.CommandType;
                    command.CommandText = commandInfo.Text.Render(logEvent);

                    try
                    {
                        installationContext.Trace("Executing {0} '{1}'", command.CommandType, command.CommandText);
                        command.ExecuteNonQuery();
                    }
                    catch (Exception exception)
                    {
                        if (exception.MustBeRethrown())
                        {
                            throw;
                        }

                        if (commandInfo.IgnoreFailures || installationContext.IgnoreFailures)
                        {
                            installationContext.Warning(exception.Message);
                        }
                        else
                        {
                            installationContext.Error(exception.Message);
                            throw;
                        }
                    }
                }
            }
            finally 
            {
                this.CloseConnection();
            }
        }

        /// <summary>
        /// Performs installation which requires administrative permissions.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        public void Install(InstallationContext installationContext)
        {
            // categories must be installed together, so we must find all PerfCounter targets in the configuration file
            var countersByCategory = this.LoggingConfiguration.AllTargets.OfType<PerformanceCounterTarget>().BucketSort(c => c.CategoryName);
            string categoryName = this.CategoryName;

            if (countersByCategory[categoryName].Any(c => c.created))
            {
                installationContext.Trace("Category '{0}' has already been installed.", categoryName);
                return;
            }

            try
            {
                PerformanceCounterCategoryType categoryType;
                CounterCreationDataCollection ccds = GetCounterCreationDataCollection(countersByCategory[this.CategoryName], out categoryType);

                if (PerformanceCounterCategory.Exists(categoryName))
                {
                    installationContext.Debug("Deleting category '{0}'", categoryName);
                    PerformanceCounterCategory.Delete(categoryName);
                }

                installationContext.Debug("Creating category '{0}' with {1} counter(s) (Type: {2})", categoryName, ccds.Count, categoryType);
                foreach (CounterCreationData c in ccds)
                {
                    installationContext.Trace("  Counter: '{0}' Type: ({1}) Help: {2}", c.CounterName, c.CounterType, c.CounterHelp);
                }

                PerformanceCounterCategory.Create(categoryName, "Category created by NLog", categoryType, ccds);
            }
            catch (Exception exception)
            {
                if (exception.MustBeRethrown())
                {
                    throw;
                }

                if (installationContext.IgnoreFailures)
                {
                    installationContext.Warning("Error creating category '{0}': {1}", categoryName, exception.Message);
                }
                else
                {
                    installationContext.Error("Error creating category '{0}': {1}", categoryName, exception.Message);
                    throw;
                }
            }
            finally
            {
                foreach (var t in countersByCategory[categoryName])
                {
                    t.created = true;
                }
            }
        }

 /// <summary>
 /// Performs uninstallation which requires administrative permissions.
 /// </summary>
 /// <param name="installationContext">The installation context.</param>
 public void Uninstall(InstallationContext installationContext)
 {
     this.RunInstallCommands(installationContext, this.UninstallDdlCommands);
 }

 /// <summary>
 /// Determines whether the item is installed.
 /// </summary>
 /// <param name="installationContext">The installation context.</param>
 /// <returns>
 /// Value indicating whether the item is installed or null if it is not possible to determine.
 /// </returns>
 public bool? IsInstalled(InstallationContext installationContext)
 {
     return null;
 }

        /// <summary>
        /// Determines whether the item is installed.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        /// <returns>
        /// Value indicating whether the item is installed or null if it is not possible to determine.
        /// </returns>
        public bool? IsInstalled(InstallationContext installationContext)
        {
            var fixedSource = GetFixedSource();

            if (!string.IsNullOrEmpty(fixedSource))
            {
                return EventLog.SourceExists(fixedSource, this.MachineName);
            }
            InternalLogger.Debug("Unclear if event source exists because it contains layout renderers");
            return null; //unclear! 
        }

        /// <summary>
        /// Performs uninstallation which requires administrative permissions.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        public void Uninstall(InstallationContext installationContext)
        {
            var fixedSource = GetFixedSource();

            if (string.IsNullOrEmpty(fixedSource))
            {
                InternalLogger.Debug("Skipping removing of event source because it contains layout renderers");
            }
            else
            {
                EventLog.DeleteEventSource(fixedSource, this.MachineName);
            }
        }

        /// <summary>
        /// Performs installation which requires administrative permissions.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        public void Install(InstallationContext installationContext)
        {
            var fixedSource = GetFixedSource();

            //always throw error to keep backwardscomp behavior.
            CreateEventSourceIfNeeded(fixedSource, true);
        }

        /// <summary>
        /// Uninstalls target-specific objects from current system.
        /// </summary>
        /// <param name="installationContext">The installation context.</param>
        /// <remarks>
        /// Uninstallation typically runs with administrative permissions.
        /// </remarks>
        public void Uninstall(InstallationContext installationContext)
        {
            if (installationContext == null)
            {
                throw new ArgumentNullException("installationContext");
            }

            this.InitializeAll();

            foreach (IInstallable installable in EnumerableHelpers.OfType<IInstallable>(this.configItems))
            {
                installationContext.Info("Uninstalling '{0}'", installable);

                try
                {
                    installable.Uninstall(installationContext);
                    installationContext.Info("Finished uninstalling '{0}'.", installable);
                }
                catch (Exception exception)
                {
                    if (exception.MustBeRethrown())
                    {
                        throw;
                    }

                    installationContext.Error("Uninstallation of '{0}' failed: {1}.", installable, exception);
                }
            }
        }