c# linq update单个字段

1.更新单个字段

/// <summary>

        /// 更新字段

        /// </summary>

        /// <typeparam name="T"></typeparam>

        /// <param name="conditions">where 筛选对象</param>

        /// <param name="updateLamda">更新字段</param>

        /// <returns></returns>

        public IEnumerable<T> Update<T>( Expression<Func<T, bool>> conditions,Func<T, dynamic> updateLamda) where T : ModelBase

        {

            List<T> setList;

            if (conditions!=null)

            {

                setList= this.Set<T>().Where(conditions).ToList();

            }

            else

            {

                setList = this.Set<T>().ToList();

            }

            foreach (var item in setList)

            {

                SetValue<T>(item, updateLamda);

                this.Entry<T>(item).State = EntityState.Modified;

            }

            this.SaveChanges();

            return setList;

        }

        public dynamic SetValue<T>(T entity, Func<T, dynamic> expr)

        {

            return expr(entity);

        }

更新单个字段

action中的使用：

public ActionResult Edit()

        {

            using (ActivityDbContext dbContext = new ActivityDbContext())

            {

                 dbContext.Update<Order>(u => u.ID==1,u =>u.UserName= u.OrderNumber.Replace("1", "xx"));
//第一个lambda表达式是用来筛选的，第二个则是进行替换的，在方法编写里面，用了dynamic动态对象，因为没办法确定改了哪个属性，只不过暂时只能改一个，改多个还不会(-_-)

            }

            return View();

        }

2.lambda修改对象的属性

public dynamic SetValue<T>(T entity, Func<T, dynamic> expr)

        {

            return expr(entity);

        }

添加对象自身方法

    public static class UpdateObject

    {

        public static dynamic SetValue2<T>(this T obj, Func<T, dynamic> expr)

        {

            return expr(obj);

        }

        public static dynamic SetValue2<T>(this T obj, List<Func<T, dynamic>> expr)

        {

            foreach (var item in expr)

            {

                item(obj);

            }

            return obj;

        }

    }

     class Program

     {

         static void Main(string[] args)

         {

             #region 修改对象属性方法

             GetProperty p = new GetProperty() { Name1 = "" };

             //SetValue<GetProperty>(p, u => u.Name1 = "2");

             Console.WriteLine(p.Name1);

             //p.SetValue2<GetProperty>(u => u.Name2 = u.Name2 + 1 + 2);

             p.SetValue2<GetProperty>(new List<Func<GetProperty, dynamic>>() { new Func<GetProperty, dynamic>(u => u.Name2 = u.Name2 + ), new Func<GetProperty, dynamic>(u => u.Name3 = u.Name3 + ) });

             Console.WriteLine(p.Name2);

             Console.WriteLine(p.Name3);

             #endregion

             Console.ReadKey();

         }

         public static string GetPropertyName<T>(Expression<Func<T,string>> expr)

         {

             var name = ((MemberExpression)expr.Body).Member.Name;

             return name;

         }

         public static dynamic SetValue<T>(T entity, Func<T, dynamic> expr)

         {

             return expr(entity);

         }

         public static dynamic SetValue<T>(T entity,List< Func<T, dynamic>> expr)

         {

             foreach (var item in expr)

             {

                 item(entity);

             }

             return entity;

         }

     }

     public static class UpdateObject

     {

         public static dynamic SetValue2<T>(this T obj, Func<T, dynamic> expr)

         {

             return expr(obj);

         }

         public static dynamic SetValue2<T>(this T obj, List<Func<T, dynamic>> expr)

         {

             foreach (var item in expr)

             {

                 item(obj);

             }

             return obj;

         }

     }

     public class GetProperty{

         public string Name1 { get; set; }

         public string Name2 { get; set; }

         public string Name3 { get; set; }

     }

控制台-修改对象属性

巴特西

c# linq update单个字段

最新文章

热门文章