IEventSource Interface

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Defines the events raised by the build engine. Loggers receive an object implementing this interface in their Initialize method and use it to subscribe to the events they are interested in receiving.

MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.

Namespace:  Microsoft.Build.Framework
Assembly:  Microsoft.Build.Framework (in Microsoft.Build.Framework.dll)

Syntax

'Declaration
Public Interface IEventSource

public interface IEventSource

public interface class IEventSource

type IEventSource =  interface end

public interface IEventSource

The IEventSource type exposes the following members.

Events

  Name Description
Public event AnyEventRaised Occurs when a build raises any other type of build event.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event BuildFinished Occurs when a build finishes.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event BuildStarted Occurs when a build starts.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event CustomEventRaised Occurs when a build raises a custom event.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event ErrorRaised Occurs when a build raises an error.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event MessageRaised Occurs when a build raises a message.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event ProjectFinished Occurs when a project finishes building.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event ProjectStarted Occurs when a project starts building.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event StatusEventRaised Occurs when a build raises a status event.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event TargetFinished Occurs when a target finishes building.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event TargetStarted Occurs when a target starts building.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event TaskFinished Occurs when a task completes execution.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event TaskStarted Occurs when a task begins execution.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.
Public event WarningRaised Occurs when a build raises a warning.MSBuild is now included in Visual Studio instead of the .NET Framework. You can use MSBuild 12.0 side-by-side with versions previously deployed with the .NET Framework.For more information, see What's New in MSBuild 12.0.

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Examples

The following example shows how to write a basic logger that responds to build events.

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;
    }
}

See Also

Reference

Microsoft.Build.Framework Namespace