正确方法

while (!Debugger.IsAttached) {
                Thread.Sleep(1000);
}
//下面开始你的代码

以下2中检测调试都无效

 [DllImport("kernel32.dll", SetLastError = true, ExactSpelling = true)]
 private static extern bool IsDebuggerPresent();
 [DllImport("kernel32.dll", SetLastError = true, ExactSpelling = true)]
 static extern bool CheckRemoteDebuggerPresent(IntPtr hProcess, ref bool isDebuggerPresent);