C# 动态泛型参数

Question

when I write a function with a generic like this

Task<ResultModel<bool>> CancelScheduledTask<T>(string scheduledTaskId, int year, int week) where T : TaskModel;

You have to provide the generic, because it can't be derived from the parameters

    switch (TaskType)
    {
        case Schedule.ROUTINE:
            cancelRoutineResult = await _taskRepository.CancelScheduledTask<RoutineTask>(TaskId, Year, Week);
            break;

        case Schedule.EVENT:
            cancelRoutineResult = await _taskRepository.CancelScheduledTask<EventTask>(TaskId, Year, Week);
            break;
    }  

Would it be possible to write this without the switch of an if else statement? something like this example which doesn't work

await _taskRepository.CancelScheduledTask<TaskType.TypeOfTask()>(TaskId, Year, Week);

public static Type TypeOfTask(this string taskType)
    {
        switch (taskType)
        {
            case Schedule.ROUTINE:
                return typeof(ScheduledRoutineModel);

            case Schedule.EVENT:
                return typeof(ScheduledEvent);

            default:
                return null;
        }
    }

Answer 1

If not performance dependent,

MethodInfo methodInfo = _taskRepository.GetType().GetMethod("CancelScheduledTask").MakeGenericMethod(TaskType.TypeOfTask());
await (methodInfo.Invoke(_taskRepository, new[] { TaskId, Year, Week }) as Task<ResultModel<bool>>);