DT转实体

Posted 2021-03-22 yzm97

  1     #region SqlDataReader 转实体
  2         /// <summary>
  3         /// SqlDataReader 转实体
  4         /// </summary>
  5         /// <typeparam name="T"></typeparam>
  6         /// <param name="row"></param>
  7         /// <returns></returns>
  8         private  T SqlDataReaderToModel<T>(DataRow row)
  9         {
 10             try
 11             {
 12                 T model;
 13                 var type = typeof(T);
 14                 model = Activator.CreateInstance<T>();
 15                 var modelPropertyInfos = type.GetProperties();
 16                 //遍历model每一个属性并赋值SqlDataReader对应的列
 17                 foreach (var pop in modelPropertyInfos)
 18                 {
 19                     try
 20                     {
 21                         //获取属性名称
 22                         var name = pop.Name;
 23                         if (pop.IsDefined(typeof(NameconversionAttr), true))//判断属性成员中是否有此特性包括继承过来的特性
 24                         {
 25 
 26                             foreach (NameconversionAttr attribute in pop.GetCustomAttributes(typeof(NameconversionAttr), true))//实例特性
 27                             {
 28                                 name = attribute.GetName();
 29                             }
 30                             if (name.Contains("序号"))
 31                             {
 32                                 continue;
 33                             }
 34                             else if (name.Contains("分类"))
 35                             {
 36                                 var value = db.DeviceCategory.ToList();
 37                                 var aname = (string)row[name];
 38                                 row.BeginEdit();//开始编辑行
 39                                 row[name] = (int)value.Where(x => x.DeviceCategoryName == aname).FirstOrDefault().Id;//给行的列"columnname"赋值
 40                                 row.EndEdit();//结束编辑
 41                                               //建议值
 42 
 43                             }
 44                         }
 45                         var popType = GetModelType(pop.PropertyType);
 46                         switch (popType)
 47                         {
 48                             case ModelType.Struct:
 49                                 {
 50                                     var fiType = pop.PropertyType;
 51                                     if (fiType == typeof(DateTime))
 52                                     {
 53                                         pop.SetValue(model, Convert.ToDateTime(row[name]));
 54                                     }
 55                                     else if (fiType == typeof(Int32))
 56                                     {
 57                                         pop.SetValue(model, Convert.ToInt32(row[name]));
 58                                     }
 59                                     else if (fiType == typeof(decimal))
 60                                     {
 61                                         var s = row[name];
 62                                         if (string.IsNullOrWhiteSpace(s.ToString()))
 63                                         {
 64                                             pop.SetValue(model, 0.0m);
 65                                         }
 66                                         else
 67                                         {
 68                                             pop.SetValue(model, Convert.ToDecimal(row[name]));
 69                                         }
 70                                     }
 71                                     else
 72                                     {
 73                                         pop.SetValue(model, row[name] == DBNull.Value ? null : row[name]);
 74                                     }
 75                                 }
 76                                 break;
 77                             case ModelType.Enum:
 78                                 {
 79                                   var fiType = pop.PropertyType; 
 80                                     if (fiType == typeof(int))
 81                                     {
 82                                         pop.SetValue(model, row[name]);
 83                                     }
 84                                     else if (fiType == typeof(string))
 85                                     {
 86                                         var value = (T)Enum.Parse(typeof(T), row[name].ToString());
 87                                         if (value != null)
 88                                             pop.SetValue(model, value);
 89                                     }
 90                                     else if (fiType == typeof(DateTime))
 91                                     {
 92                                         var value = (T)Enum.Parse(typeof(T), row[name].ToString());
 93                                         if (value != null)
 94                                             pop.SetValue(model, Convert.ToDateTime(value));
 95                                     }
 96 
 97                                 }
 98                                 break;
 99                             case ModelType.Boolen:
100                                 bool? Value = null;
101                                 if (row[name] != DBNull.Value) Value = Convert.ToBoolean(row[name]);
102                                 pop.SetValue(model, Value);
103                                 break;
104                             case ModelType.String:
105                                 {
106                                     pop.SetValue(model, row[name] == DBNull.Value ? null : row[name]);
107                                 }
108                                 break;
109                             case ModelType.Object:
110                                 {
111                                     pop.SetValue(model, row[name] == DBNull.Value ? null : row[name]);
112                                 }
113                                 break;
114                             case ModelType.Else:
115                                 throw new Exception("不支持该类型转换");
116                             default:
117                                 throw new Exception("未知类型");
118                         }
119                     }
120                     catch (Exception ex)
121                     {
122                         pop.SetValue(model,default(T));
123 
124                     }
125                 }
126                 return model;
127             }
128             catch (Exception ex)
129             {
130                 throw ex;
131             }
132         }
133         /// <summary>
134         /// 类型枚举
135         /// </summary>
136         private enum ModelType
137         {
138             //值类型
139             Struct,
140             Enum,
141             Boolen,
142             //引用类型
143             String,
144             Object,
145             Else,
146 
147 
148         }
149         private static ModelType GetModelType(Type modelType)
150         {
151             if (modelType.IsEnum)
152             {
153                 return ModelType.Enum;
154             }
155             if (modelType == typeof(bool))
156             {
157                 return ModelType.Boolen;
158             }
159             //值类型
160             if (modelType.IsValueType)
161             {
162                 return ModelType.Struct;
163             }
164             //引用类型 特殊类型处理
165             if (modelType == typeof(string))
166             {
167                 return ModelType.String;
168             }
169             //引用类型 特殊类型处理
170             return modelType == typeof(object) ? ModelType.Object : ModelType.Else;
171         }
172         #endregion