执行错误！ 模块:Home 功能：teacher_info  System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation.
 ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at Home.teacher_info() in D:\Web\ISnaiWeb\ISnaiWeb\controller\Home.cs:line 3290
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Span`1& arguments, Signature sig, Boolean constructor, Boolean wrapExceptions)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.RuntimeType.InvokeMember(String name, BindingFlags bindingFlags, Binder binder, Object target, Object[] providedArgs, ParameterModifier[] modifiers, CultureInfo culture, String[] namedParams)
   at Program.<>c__DisplayClass0_0.<<Main>$>b__1(HttpContext context) in D:\Web\ISnaiWeb\ISnaiWeb\Program.cs:line 119