如何从.Net中的字符串验证模型/类的属性？

Question

我有一个web api控制器，它通过字符串扩展Linq动态来做ApplySort。

我可以通过几个排序，即: sort=id，名称，日期创建到这个web api中。但是在做Linq之前，我需要验证这些字符串(Id、Name、DateCreated等)存在于模型/类的属性中。我该怎么做？

[HttpGet]
[Route("api/Activities/{sort=id}/{pagenumber=1}/{pagesize=10}")]
[CacheOutput(ClientTimeSpan = 60, ServerTimeSpan = 60)]
public async Task<IHttpActionResult> GetActivities(string sort, int pageNumber, int pageSize)
{
    string userId = User.Identity.GetUserId();

    var activities = await (db.Activities.Where(q => q.UserId == userId)
                              .AsQueryable().ApplySort(sort)
                              .Skip((pageNumber - 1) * pageSize)
                              .Take(pageSize)).ToListAsync();

    return Ok(activities);
}

Answer 1

您可以使用GetProperties()：

[HttpGet]
[Route("api/Activities/{sort=id}/{pagenumber=1}/{pagesize=10}")]
[CacheOutput(ClientTimeSpan = 60, ServerTimeSpan = 60)]
public async Task<IHttpActionResult> GetActivities(string sort, int pageNumber, int pageSize)
{
    string userId = User.Identity.GetUserId();

    var propertyNames = typeof (Activity).GetProperties().Select(p=>p.Name).ToList();
    var sorts = sort.Split(',').Select(s=> s.Trim());
    foreach(var sortPart in sorts)
    {
       if(propertyNames.IndexOf(sortPart)<0)
       {
          throw//what ever should be done in error-case
       }
    }
    var activities = await (db.Activities.Where(q => q.UserId == userId)
                              .AsQueryable().ApplySort(sort)
                              .Skip((pageNumber - 1) * pageSize)
                              .Take(pageSize)).ToListAsync();

    return Ok(activities);
}