C# 对象复制
/// <summary> /// 把DataTable对象转成List<T>对象 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="table"></param> /// <returns></returns> public static List<T> ConvertToModel<T>(this DataTable table) where T : new() { var list = new List<T>(); PropertyInfo[] propertys = typeof(T).GetProperties(); foreach (DataRow row in table.Rows) { T model = Activator.CreateInstance<T>(); foreach (PropertyInfo pi in propertys) { var tempName = pi.Name; if (!table.Columns.Contains(tempName)) continue; if (!pi.CanWrite) continue; object value = Convert.ToString(row[tempName]); if (value != DBNull.Value) { pi.SetValue(model, value, null); } } list.Add(model); } return list; } /// <summary> /// 把具有同结构的实体赋值到另外一个实体 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="from"></param> /// <returns></returns> public static T ConvertTo<T>(this object from) where T : new() { if (from == null) { return default(T); } var to = Activator.CreateInstance<T>(); return from.CopyTo<T>(to); } /// <summary> /// 通过比较属性名称来给目标实体赋值 /// </summary> /// <typeparam name="T">泛型实体</typeparam> /// <param name="from">原实体</param> /// <param name="to">目标实体</param> /// <returns></returns> public static T CopyTo<T>(this object from, T to) where T : new() { if (from == null) { return to; } if (to == null) { to = Activator.CreateInstance<T>(); } PropertyDescriptorCollection fromProperties = TypeDescriptor.GetProperties(from); PropertyDescriptorCollection toProperties = TypeDescriptor.GetProperties(to); foreach (PropertyDescriptor fromProperty in fromProperties) { PropertyDescriptor toProperty = toProperties.Find(fromProperty.Name, true); if (toProperty != null && !toProperty.IsReadOnly) { bool isDirectlyAssignable = toProperty.PropertyType.IsAssignableFrom(fromProperty.PropertyType); bool liftedValueType = !isDirectlyAssignable && Nullable.GetUnderlyingType(fromProperty.PropertyType) == toProperty.PropertyType; if (isDirectlyAssignable || liftedValueType) { object fromValue = fromProperty.GetValue(from); if (isDirectlyAssignable || (fromValue != null && liftedValueType)) { toProperty.SetValue(to, fromValue); } } } } return to; } /// <summary> /// 把实体转换成一个dynamic对象 /// </summary> /// <param name="value"></param> /// <returns></returns> public static dynamic ToDynamic(this object value) { IDictionary<string, object> expando = new ExpandoObject(); foreach (PropertyDescriptor property in TypeDescriptor.GetProperties(value.GetType())) { expando.Add(property.Name, property.GetValue(value)); } return expando as ExpandoObject; }
posted on 2019-02-27 13:50 wangzhiliang 阅读(319) 评论(0) 编辑 收藏 举报