TraceSwitch.TraceWarning 属性   
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
获取一个值,它指示开关是否允许警告消息。
public:
 property bool TraceWarning { bool get(); };public bool TraceWarning { get; }member this.TraceWarning : boolPublic ReadOnly Property TraceWarning As Boolean属性值
如果 Level 属性设置为 Warning、Info 或 Verbose,则为 true;否则为 false。
示例
下面的代码示例创建一个新的 TraceSwitch ,并使用 开关确定是否发出错误消息。 开关是在类级别创建的。 
              MyMethod如果 属性设置为 TraceLevel.Warning 或更高版本,Level则写入第一条错误消息。 但是, MyMethod 当 小于 TraceLevel.Verbose时Level,不会写入第二条错误消息。
   // Class-level declaration.
   /* Create a TraceSwitch to use in the entire application.*/
private:
   static TraceSwitch^ mySwitch = gcnew TraceSwitch( "General", "Entire Application" );
public:
   static void MyMethod()
   {
      // Write the message if the TraceSwitch level is set to Warning or higher.
      if ( mySwitch->TraceWarning )
         Console::WriteLine( "My error message." );
      // Write the message if the TraceSwitch level is set to Verbose.
      if ( mySwitch->TraceVerbose )
         Console::WriteLine( "My second error message." );
   }
   static void main()
   {
      // Run the method that prints error messages based on the switch level.
      MyMethod();
   }
//Class-level declaration.
/* Create a TraceSwitch to use in the entire application.*/
static TraceSwitch mySwitch = new TraceSwitch("General", "Entire Application");
static public void MyMethod()
{
    // Write the message if the TraceSwitch level is set to Warning or higher.
    if (mySwitch.TraceWarning)
        Console.WriteLine("My error message.");
    // Write the message if the TraceSwitch level is set to Verbose.
    if (mySwitch.TraceVerbose)
        Console.WriteLine("My second error message.");
}
public static void Main(string[] args)
{
    // Run the method that prints error messages based on the switch level.
    MyMethod();
}
' Class-level declaration.
' Create a TraceSwitch to use in the entire application. 
Private Shared mySwitch As New TraceSwitch("General", "Entire Application")    
Public Shared Sub MyMethod()
    ' Write the message if the TraceSwitch level is set to Warning or higher.
    If mySwitch.TraceWarning Then
        Console.WriteLine("My error message.")
    End If 
    ' Write the message if the TraceSwitch level is set to Verbose.
    If mySwitch.TraceVerbose Then
        Console.WriteLine("My second error message.")
    End If
End Sub
Public Shared Sub Main()
    ' Run the method that prints error messages based on the switch level.
    MyMethod()
End Sub
注解
可以将 TraceError、 TraceWarning、 TraceInfo和 TraceVerbose 属性与 Debug 和 Trace 类结合使用,以发出具有指定重要性或更大值的所有消息。 当 属性 Level 设置为 TraceLevel.Warning时,会发出警告和错误处理消息。