生成记录器
使用记录器可以自定义生成的输出，并显示消息、错误或警告以响应特定生成事件。 每个记录器都实现为实现 ILogger 接口的 .NET 类，该接口在 Microsoft.Build.Framework.dll 程序集中定义。
实现记录器可以采用两种方法：
直接实现 ILogger 接口。
从帮助器类 Logger 派生您的类，该帮助器类在 Microsoft.Build.Utilities.dll 程序集中定义。 Logger 实现 ILogger 并提供某些 ILogger 成员的默认实现。
本主题将介绍如何编写一个简单的记录器，该记录器从 Logger 派生，并在控制台上显示消息以响应特定生成事件。
注册事件
记录器的用途是收集生成引擎所报告的有关生成过程的信息，然后以有用的方式报告这些信息。 所有的记录器都必须重写 Initialize 方法，即记录器用来注册事件的方法。 在本示例中，记录器注册 TargetStarted、ProjectStarted 和 ProjectFinished 事件。
public class MySimpleLogger : Logger
{
public override void Initialize(Microsoft.Build.Framework.IEventSource eventSource)
{
//Register for the ProjectStarted, TargetStarted, and ProjectFinished events
eventSource.ProjectStarted += new ProjectStartedEventHandler(eventSource_ProjectStarted);
eventSource.TargetStarted += new TargetStartedEventHandler(eventSource_TargetStarted);
eventSource.ProjectFinished += new ProjectFinishedEventHandler(eventSource_ProjectFinished);
}
响应事件
记录器注册特定的事件后，就需要在发生这些事件时处理它们。 对于 ProjectStarted 和 ProjectFinished 事件，记录器只写入一个短语以及事件中涉及的项目文件的名称。 所有来自记录器的消息都被写到控制台窗口。
void eventSource_ProjectStarted(object sender, ProjectStartedEventArgs e)
{
Console.WriteLine("Project Started: " + e.ProjectFile);
}
void eventSource_ProjectFinished(object sender, ProjectFinishedEventArgs e)
{
Console.WriteLine("Project Finished: " + e.ProjectFile);
}
响应记录器详细级别值
在某些情况下，如果 MSBuild.exe 的 /verbosity 开关包含特定的值，可能需要仅记录来自某个事件的信息。 在本示例中，如果 Verbosity 属性（该属性由 /verbosity 开关设置）等于 LoggerVerbosity Detailed，TargetStarted 事件处理程序将仅记录一条消息。
void eventSource_TargetStarted(object sender, TargetStartedEventArgs e)
{
if (Verbosity == LoggerVerbosity.Detailed)
{
Console.WriteLine("Target Started: " + e.TargetName);
}
}
指定记录器
在将记录器编译为程序集后，需要通知 MSBuild 在生成过程中使用该记录器。 这是通过对 MSBuild.exe 使用 /logger 开关来完成的。 有关可用于 MSBuild.exe 的开关的更多信息，请参见 MSBuild 命令行参考。
下面的命令行生成项目 MyProject.csproj 并使用在 SimpleLogger.dll 中实现的记录器类。 /nologo 开关隐藏版权标志和版权信息，而 /noconsolelogger 开关禁用默认的 MSBuild 控制台记录器。
MSBuild /nologo /noconsolelogger /logger:SimpleLogger.dll
下面的命令行使用相同的记录器生成项目，但是 Verbosity 级别为 Detailed。
MSBuild /nologo /noconsolelogger /logger:SimpleLogger.dll /verbosity:Detailed
示例
.gif "ms171471.collapse_all(zh-cn,VS.110).gif")
说明
下面的示例包含记录器的完整代码。
代码
using System;
using Microsoft.Build.Utilities;
using Microsoft.Build.Framework;
namespace SimpleLogger
{
public class MySimpleLogger : Logger
{
public override void Initialize(Microsoft.Build.Framework.IEventSource eventSource)
{
//Register for the ProjectStarted, TargetStarted, and ProjectFinished events
eventSource.ProjectStarted += new ProjectStartedEventHandler(eventSource_ProjectStarted);
eventSource.TargetStarted += new TargetStartedEventHandler(eventSource_TargetStarted);
eventSource.ProjectFinished += new ProjectFinishedEventHandler(eventSource_ProjectFinished);
}
void eventSource_ProjectStarted(object sender, ProjectStartedEventArgs e)
{
Console.WriteLine("Project Started: " + e.ProjectFile);
}
void eventSource_ProjectFinished(object sender, ProjectFinishedEventArgs e)
{
Console.WriteLine("Project Finished: " + e.ProjectFile);
}
void eventSource_TargetStarted(object sender, TargetStartedEventArgs e)
{
if (Verbosity == LoggerVerbosity.Detailed)
{
Console.WriteLine("Target Started: " + e.TargetName);
}
}
}
}
示例
说明
下面的示例演示如何实现一个记录器，该记录器将日志写入文件而不是显示在控制台窗口中。
代码
using System;
using System.IO;
using System.Security;
using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;
namespace MyLoggers
{
// This logger will derive from the Microsoft.Build.Utilities.Logger class,
// which provides it with getters and setters for Verbosity and Parameters,
// and a default empty Shutdown() implementation.
public class BasicFileLogger : Logger
{
/// <summary>
/// Initialize is guaranteed to be called by MSBuild at the start of the build
/// before any events are raised.
/// </summary>
public override void Initialize(IEventSource eventSource)
{
// The name of the log file should be passed as the first item in the
// "parameters" specification in the /logger switch. It is required
// to pass a log file to this logger. Other loggers may have zero or more than
// one parameters.
if (null == Parameters)
{
throw new LoggerException("Log file was not set.");
}
string[] parameters = Parameters.Split(';');
string logFile = parameters[0];
if (String.IsNullOrEmpty(logFile))
{
throw new LoggerException("Log file was not set.");
}
if (parameters.Length > 1)
{
throw new LoggerException("Too many parameters passed.");
}
try
{
// Open the file
this.streamWriter = new StreamWriter(logFile);
}
catch (Exception ex)
{
if
(
ex is UnauthorizedAccessException
|| ex is ArgumentNullException
|| ex is PathTooLongException
|| ex is DirectoryNotFoundException
|| ex is NotSupportedException
|| ex is ArgumentException
|| ex is SecurityException
|| ex is IOException
)
{
throw new LoggerException("Failed to create log file: " + ex.Message);
}
else
{
// Unexpected failure
throw;
}
}
// For brevity, we'll only register for certain event types. Loggers can also
// register to handle TargetStarted/Finished and other events.
eventSource.ProjectStarted += new ProjectStartedEventHandler(eventSource_ProjectStarted);
eventSource.TaskStarted += new TaskStartedEventHandler(eventSource_TaskStarted);
eventSource.MessageRaised += new BuildMessageEventHandler(eventSource_MessageRaised);
eventSource.WarningRaised += new BuildWarningEventHandler(eventSource_WarningRaised);
eventSource.ErrorRaised += new BuildErrorEventHandler(eventSource_ErrorRaised);
eventSource.ProjectFinished += new ProjectFinishedEventHandler(eventSource_ProjectFinished);
}
void eventSource_ErrorRaised(object sender, BuildErrorEventArgs e)
{
// BuildErrorEventArgs adds LineNumber, ColumnNumber, File, amongst other parameters
string line = String.Format(": ERROR {0}({1},{2}): ", e.File, e.LineNumber, e.ColumnNumber);
WriteLineWithSenderAndMessage(line, e);
}
void eventSource_WarningRaised(object sender, BuildWarningEventArgs e)
{
// BuildWarningEventArgs adds LineNumber, ColumnNumber, File, amongst other parameters
string line = String.Format(": Warning {0}({1},{2}): ", e.File, e.LineNumber, e.ColumnNumber);
WriteLineWithSenderAndMessage(line, e);
}
void eventSource_MessageRaised(object sender, BuildMessageEventArgs e)
{
// BuildMessageEventArgs adds Importance to BuildEventArgs
// Let's take account of the verbosity setting we've been passed in deciding whether to log the message
if ((e.Importance == MessageImportance.High && IsVerbosityAtLeast(LoggerVerbosity.Minimal))
|| (e.Importance == MessageImportance.Normal && IsVerbosityAtLeast(LoggerVerbosity.Normal))
|| (e.Importance == MessageImportance.Low && IsVerbosityAtLeast(LoggerVerbosity.Detailed))
)
{
WriteLineWithSenderAndMessage(String.Empty, e);
}
}
void eventSource_TaskStarted(object sender, TaskStartedEventArgs e)
{
// TaskStartedEventArgs adds ProjectFile, TaskFile, TaskName
// To keep this log clean, this logger will ignore these events.
}
void eventSource_ProjectStarted(object sender, ProjectStartedEventArgs e)
{
// ProjectStartedEventArgs adds ProjectFile, TargetNames
// Just the regular message string is good enough here, so just display that.
WriteLine(String.Empty, e);
indent++;
}
void eventSource_ProjectFinished(object sender, ProjectFinishedEventArgs e)
{
// The regular message string is good enough here too.
indent--;
WriteLine(String.Empty, e);
}
/// <summary>
/// Write a line to the log, adding the SenderName and Message
/// (these parameters are on all MSBuild event argument objects)
/// </summary>
private void WriteLineWithSenderAndMessage(string line, BuildEventArgs e)
{
if (0 == String.Compare(e.SenderName, "MSBuild", true /*ignore case*/))
{
// Well, if the sender name is MSBuild, let's leave it out for prettiness
WriteLine(line, e);
}
else
{
WriteLine(e.SenderName + ": " + line, e);
}
}
/// <summary>
/// Just write a line to the log
/// </summary>
private void WriteLine(string line, BuildEventArgs e)
{
for (int i = indent; i > 0; i--)
{
streamWriter.Write("\t");
}
streamWriter.WriteLine(line + e.Message);
}
/// <summary>
/// Shutdown() is guaranteed to be called by MSBuild at the end of the build, after all
/// events have been raised.
/// </summary>
public override void Shutdown()
{
// Done logging, let go of the file
streamWriter.Close();
}
private StreamWriter streamWriter;
private int indent;
}
}