我是这个网站的新手，所以如果这没有帮助，我深表歉意.但是，当我用C#编写selenium(webdriver)测试时，我通常不使用append命令.尝试以其他方式使用控制台，例如

I'm new to this site, so i apologize if this is not helpful. However, when i am writing selenium(webdriver) tests in C#, i generally do not use the append command. Try approaching the console differently, such as

Console.WriteLine("Text you wish to be outputted to the Console"); 
//OR MAYBE 
Console.Write("Text you wish to be outputted to the Console"); 

此外，我不确定实际上是否可以同时执行两个命令，但是，您可以使输出取决于其他选定代码的执行情况，可以使用if语句，也可以尝试catch等.

In addition, i am not sure that simultaneously executing two commands is actually possible, however, you can make the output contingent upon other chosen code executing, using if statements, or maybe try catch etc.

希望这会有所帮助！干杯！

Hope that this helps! Cheers!