在web開發過程中，有時候為了數據傳輸的方便，比如：后臺需要更新前端的ViewModel，此時我們定義一個與前端ViewModel結構一樣的DTO對象，從數據層獲取數據后，將數據封裝成DTO然后序列化為json傳回前端，由于我正在開發的項目中的Model是用DataSet來實現的，不是純粹的面向對象（如果Model是對象的話可以用AutoMapper來實現轉換），所以從數據層獲取的都是DataSet或DataTable，這時需要將DataTable轉換為DTO對象，DTO對象的屬性與DataTable的列之間并不是一一對應的關系，為了轉換方便，實現了一個簡易的轉換類，代碼如下：
1 public class DtObjConverter 2 { 3 4 /// <summary> 5 /// 將DataTable轉換成對象，對象的屬性與列同名 6 /// </summary> 7 /// <typeparam name="T"></typeparam> 8 /// <param name="datatable"></param> 9 /// <returns></returns> 10 public List<T> ConvertTo<T>(DataTable datatable) where T : new() 11 { 12 List<T> Temp = new List<T>(); 13 try 14 { 15 List<string> columnsNames = new List<string>(); 16 foreach (DataColumn DataColumn in datatable.Columns) 17 columnsNames.Add(DataColumn.ColumnName); 18 Temp = datatable.AsEnumerable().ToList().ConvertAll<T>(row => getObject<T>(row, columnsNames)); 19 return Temp; 20 } 21 catch 22 { 23 return Temp; 24 } 25 26 } 27 28 /// <summary> 29 /// 將DataTable轉換成對象，對象的屬性會根據map參數進行轉換 30 /// </summary> 31 /// <typeparam name="T"></typeparam> 32 /// <param name="datatable"></param> 33 /// <param name="map"></param> 34 /// <returns></returns> 35 public List<T> ConvertTo<T>(DataTable datatable, Hashtable map) where T : new() 36 { 37 List<T> Temp = new List<T>(); 38 try 39 { 40 List<string> columnsNames = new List<string>(); 41 foreach (DataColumn DataColumn in datatable.Columns) 42 columnsNames.Add(DataColumn.ColumnName); 43 Temp = datatable.AsEnumerable().ToList().ConvertAll<T>(row => getMapObject<T>(row, columnsNames, map)); 44 return Temp; 45 } 46 catch 47 { 48 return Temp; 49 } 50 51 } 52 53 /// <summary> 54 /// 根據DataTable生成對象，對象的屬性與列同名 55 /// </summary> 56 /// <typeparam name="T"></typeparam> 57 /// <param name="row"></param> 58 /// <param name="columnsName"></param> 59 /// <returns></returns> 60 public T getObject<T>(DataRow row, List<string> columnsName) where T : new() 61 { 62 T obj = new T(); 63 try 64 { 65 string columnname = ""; 66 string value = ""; 67 PRopertyInfo[] Properties; 68 Properties = typeof(T).GetProperties(); 69 foreach (PropertyInfo objProperty in Properties) 70 { 71 columnname = columnsName.Find(name => name.ToLower() == objProperty.Name.ToLower()); 72 if (!string.IsNullOrEmpty(columnname)) 73 { 74 value = row[columnname].ToString(); 75 if (!string.IsNullOrEmpty(value)) 76 { 77 if (Nullable.GetUnderlyingType(objProperty.PropertyType) != null) 78 { 79 value = row[columnname].ToString().Replace("$", "").Replace(",", ""); 80 objProperty.SetValue(obj, Convert.ChangeType(value, Type.GetType(Nullable.GetUnderlyingType(objProperty.PropertyType).ToString())), null); 81 } 82 else 83 { 84 value = row[columnname].ToString().Replace("%", ""); 85 objProperty.SetValue(obj, Convert.ChangeType(value, Type.GetType(objProperty.PropertyType.ToString())), null); 86 } 87 } 88 } 89 } 90 return obj; 91 } 92 catch 93 { 94 return obj; 95 } 96 } 97 98 /// <summary> 99 /// 根據DataTable生成對象，對象的屬性會根據map參數進行轉換100 /// </summary>101 /// <typeparam name="T"></typeparam>102 /// <param name="row"></param>103 /// <param name="columnsName"></param>104 /// <returns></returns>105 public T getMapObject<T>(DataRow row, List<string> columnsName, Hashtable map) where T : new()106 {107 T obj = new T();108 try109 {110 string columnname = "";111 string value = "";112 PropertyInfo[] Properties;113 Properties = typeof(T).GetProperties();114 foreach (PropertyInfo objProperty in Properties)115 {116 string prpertyName = objProperty.Name;117 columnname = columnsName.Find(name => name.ToLower() == map[prpertyName].ToString().ToLower());118 if (!string.IsNullOrEmpty(columnname))119 {120 value = row[columnname].ToString();121 if (!string.IsNullOrEmpty(value))122 {123 if (Nullable.GetUnderlyingType(objProperty.PropertyType) != null)124 {125 value = row[columnname].ToString().Replace("$", "").Replace(",", "");126 objProperty.SetValue(obj, Convert.ChangeType(value, Type.GetType(Nullable.GetUnderlyingType(objProperty.PropertyType).ToString())), null);127 }128 else129 {130 value = row[columnname].ToString().Replace("%", "");131 objProperty.SetValue(obj, Convert.ChangeType(value, Type.GetType(objProperty.PropertyType.ToString())), null);132 }133 }134 }135 }136 return obj;137 }138 catch (Exception e)139 {140 string error = e.Message;141 return obj;142 }143 }144 145 public DataTable ToDataTable<T>(IEnumerable<T> collection)146 {147 DataTable newDataTable = new DataTable();148 Type impliedType = typeof(T);149 PropertyInfo[] _propInfo = impliedType.GetProperties();150 foreach (PropertyInfo pi in _propInfo)151 newDataTable.Columns.Add(pi.Name, pi.PropertyType);152 153 foreach (T item in collection)154 {155 DataRow newDataRow = newDataTable.NewRow();156 newDataRow.BeginEdit();157 foreach (PropertyInfo pi in _propInfo)158 newDataRow[pi.Name] = pi.GetValue(item, null);159 newDataRow.EndEdit();160 newDataTable.Rows.Add(newDataRow);161 }162 return newDataTable;163 }164 165 }用法：
DtObjConverterConvert convert = new DtObjConverterConvert ();//配置映射Hashtable map = new Hashtable();map.Add("Title", "name"); //key為對象屬性名，value為表列名/*----- 此處省略其他字段的添加 -----*/List<YourDTOModel> dtoModelList = convert.ConvertTo<YourDTOModel>(dt, map);新聞熱點
疑難解答
