c# - 如何以编程方式获取当前的跟踪开关？

Question

在我的 web.config 中我有:

<system.diagnostics>
  <switches>
    <add name="logLevelSwitch" value="1" />
  </switches>
</system.diagnostics>

有没有一种方法可以调用，例如:

System.Diagnostics.TraceSwitch["logLevelSwitch"]获取当前值？

Answer 1

一旦您在web.config 文件中定义了开关值，就可以通过创建一个TraceSwitch 来轻松地从您的应用程序中获取该值。同名:

private static TraceSwitch logSwitch = new TraceSwitch("logLevelSwitch",
    "This is your logLevelSwitch in the config file");

public static void Main(string[] args)
{
    // you can get its properties value then:
    Console.WriteLine("Trace switch {0} is configured as {1}",
        logSwitch.DisplayName,
        logSwitch.Level.ToString());

    // and you can use it like this:
    if (logSwitch.TraceError)
        Trace.WriteLine("This is an error");

    // or like this also:
    Trace.WriteLineIf(logSwitch.TraceWarning, "This is a warning");
}

此外，根据文档，要使其正常工作:

You must enable tracing or debugging to use a switch. The following syntax is compiler specific. If you use compilers other than C# or Visual Basic, refer to the documentation for your compiler.

To enabledebugging in C#, add the /d:DEBUG flag to the compiler command line when you compile your code, or you can add #define DEBUG to the top of your file. In Visual Basic, add the /d:DEBUG=True flag to the compiler command line.

To enable tracing using in C#, add the /d:TRACE flag to the compiler command line when you compile your code, or add #define TRACE to the top of your file. In Visual Basic, add the /d:TRACE=True flag to the compiler command line.