asp.net core ModelState 模型状态验证扩展类

 using DMS.Common.BaseResult;
 using Microsoft.AspNetCore.Mvc.ModelBinding;
 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;

 /// <summary>
 /// 聚合扩展方法类
 /// </summary>
 public static class ModelStateExts
 {
     #region [ 得到模型错误消息 NonAction Task<string> ModelStateMsg(ModelStateDictionary modelState, List<string> PartValidKeys = null) ]

     /// <summary>
     /// 得到模型错误消息
     /// <code>
     /// <![CDATA[
     ///     if (ModelState.IsValidOK(out string errmsg))
     ///     {
     ///         return await Service.GetLiveVodAndVideoProductList(CurrentUserTicket.ID.ToLong(), param);
     ///     }
     ///     else
     ///     {
     ///         return new ResponsePageResult<ProductVodOrVideoResult> { errno = 1, errmsg = errmsg };
     ///     }
     /// ]]>
     /// </code>
     /// </summary>
     /// <param name="modelState"></param>
     /// <param name="errmsg">返回的错误消息</param>
     /// <param name="PartValidKeys">要验证的属性集合</param>
     /// <returns></returns>
     public static bool IsValidOK(this ModelStateDictionary modelState, out string errmsg, List<string> PartValidKeys = null)
     #region [ MyRegion ]
     {
         var errorCount = ;

         List<string> sb = new List<string>();
         //获取所有错误的Key
         List<string> keys = PartValidKeys ?? modelState.Keys.ToList();

         //获取每一个key对应的ModelStateDictionary
         foreach (var key in keys)
         {
             var errors = modelState[key].Errors.ToList();
             errorCount += errors.Count;

             //将错误描述添加到sb中
             foreach (var error in errors)
             {
                 sb.Add(error.ErrorMessage);
             }
         }

         var result = string.Join("，", sb);
         if (string.IsNullOrWhiteSpace(result))
         {
             result = $"{result}。";
         }

         errmsg = result;

         return errorCount >  ? false : true;
     }
     #endregion

     #endregion

     #region [ 进行模型验证，并返回服务结果 ]

     /// <summary>
     /// 执行模型验证，并返回指定服务方法的执行结果
     /// 调用方式：return await ModelState.GetResult(Service.ActionName, param);
     /// </summary>
     /// <typeparam name="TParam"></typeparam>
     /// <typeparam name="TResult"></typeparam>
     /// <param name="modelState"></param>
     /// <param name="func"></param>
     /// <param name="param"></param>
     /// <param name="PartValidKeys"></param>
     /// <returns></returns>
     public async static Task<TResult> Execute<TParam, TResult>(this ModelStateDictionary modelState, Func<TParam, Task<TResult>> func, TParam param, List<string> PartValidKeys = null) where TResult : class, new()
         #region [ MyRegion ]
     {
         if (IsValidOK(modelState, out string errmsg, PartValidKeys: PartValidKeys))
         {
             var result = new TResult { };

             return await func.Invoke(param);
         }
         else
         {
             return new DataResultBase { errno = , errmsg = errmsg } as TResult;
         }
     }
     #endregion

     #endregion
 }