C#DataTable(转List /JSON/字典 互转)

  1    #region  数据表DataTable 转键值对集合 List
  2         /// <summary> 
  3         /// 数据表DataTable 转键值对集合 List
  4         /// 把DataTable转成 List集合, 存每一行 
  5         /// 集合中放的是键值对字典,存每一列 
  6         /// </summary> 
  7         /// <param name="dt">数据表</param> 
  8         /// <returns>哈希表数组</returns> 
  9         public static List<Dictionary<string, object>> DataTableToList(DataTable dt)
 10         {
 11             List<Dictionary<string, object>> list
 12                  = new List<Dictionary<string, object>>();
 13 
 14             foreach (DataRow dr in dt.Rows)
 15             {
 16                 Dictionary<string, object> dic = new Dictionary<string, object>();
 17                 foreach (DataColumn dc in dt.Columns)
 18                 {
 19                     dic.Add(dc.ColumnName, dr[dc.ColumnName]);
 20                 }
 21                 list.Add(dic);
 22             }
 23             return list;
 24         }
 25         #endregion
 26 
 27         #region 数据集转键值对数组字典
 28 
 29         /// <summary> 
 30         /// 数据集转键值对数组字典 
 31         /// </summary> 
 32         /// <param name="dataSet">数据集</param> 
 33         /// <returns>键值对数组字典</returns> 
 34         public static Dictionary<string, List<Dictionary<string, object>>> DataSetToDic(DataSet ds)
 35         {
 36             Dictionary<string, List<Dictionary<string, object>>> result = new Dictionary<string, List<Dictionary<string, object>>>();
 37 
 38             foreach (DataTable dt in ds.Tables)
 39                 result.Add(dt.TableName, DataTableToList(dt));
 40 
 41             return result;
 42         }
 43         #endregion
 44 
 45         #region 数据表Tables 转JSON
 46         /// <summary> 
 47         /// 数据表转Tables JSON 
 48         /// </summary> 
 49         /// <param name="dataTable">数据表</param> 
 50         /// <returns>JSON字符串</returns> 
 51         public static string DataTableToJSON(DataTable dt)
 52         {
 53             return JsonHelper.ObjectToJSON(DataTableToList(dt));
 54         }
 55         #endregion
 56 
 57         #region 将datatable转换为json
 58         /// <summary>
 59         /// 将datatable转换为json  
 60         /// </summary>
 61         /// <param name="dtb">Dt</param>
 62         /// <returns>JSON字符串</returns>
 63         public static string Dtb2Json(DataTable dtb)
 64         {
 65             //JavaScriptSerializer jss = new JavaScriptSerializer();
 66 
 67             System.Collections.ArrayList dic = new System.Collections.ArrayList();
 68 
 69             foreach (DataRow dr in dtb.Rows)
 70             {
 71                 System.Collections.Generic.Dictionary<string, object> drow = new System.Collections.Generic.Dictionary<string, object>();
 72 
 73                 foreach (DataColumn dc in dtb.Columns)
 74                 {
 75                     drow.Add(dc.ColumnName, dr[dc.ColumnName]);
 76                 }
 77 
 78                 dic.Add(drow);
 79             }
 80 
 81             return null;
 82         }
 83         #endregion
 84 
 85         #region 将Dictionary转换为数据表数据 Tables
 86         public static DataTable DictToDataTable(Dictionary<string, object> dict)
 87         {
 88             DataTable dt = new DataTable();
 89 
 90             //dt.Columns.Add("ID", typeof(Guid));
 91             //dt.Columns.Add("DID", typeof(string));
 92             //dt.Columns.Add("DEPARTMENTNUM", typeof(string));
 93             //dt.Columns.Add("DEPARTMENTNAME", typeof(string));
 94             //dt.Columns.Add("REMARKS", typeof(string));
 95 
 96             foreach (var colName in dict.Keys)
 97             {
 98                 dt.Columns.Add(colName, typeof(string));
 99             }
100             DataRow dr = dt.NewRow();
101             foreach (KeyValuePair<string, object> item in dict)
102             {
103                 dr[item.Key] = item.Value;
104             }
105             dt.Rows.Add(dr);
106             return dt;
107         }
108         #endregion
109 
110         #region 将List转换为数据表数据 Tables
111         /// <summary>
112         /// List转DataTable
113         /// </summary>
114         public static DataTable ListToDataTable<T>(List<T> list)
115         {
116             if (list == null || list.Count == 0)
117             {
118                 return new DataTable();
119             }
120 
121             //获取T下所有的属性
122             Type entityType = list[0].GetType();
123             PropertyInfo[] entityProperties = entityType.GetProperties();
124 
125             DataTable dt = new DataTable("data");
126 
127             for (int i = 0; i < entityProperties.Length; i++)
128             {
129                 dt.Columns.Add(entityProperties[i].Name);
130             }
131 
132             foreach (var item in list)
133             {
134                 if (item.GetType() != entityType)
135                 {
136                     throw new Exception("要转换集合元素类型不一致!");
137                 }
138                 //创建一个用于放所有属性值的数组
139                 object[] entityValues = new object[entityProperties.Length];
140                 for (int i = 0; i < entityProperties.Length; i++)
141                 {
142                     entityValues[i] = entityProperties[i].GetValue(item, null);
143                 }
144 
145                 dt.Rows.Add(entityValues);
146             }
147             return dt;
148         }
149         #endregion
150 
151         #region  Json 字符串 转换为 DataTable数据集合  简要版,正在使用中
152         /// <summary>
153         /// Json 字符串 转换为 DataTable数据集合  简要版,正在使用中
154         /// </summary>
155         /// <param name="json"></param>
156         /// <returns></returns>
157         /// 
158         //格式;
159         //[{"mac":"20:f1:7c:c5:cd:80","rssi":"-86","ch":"9"},{"mac":"20:f1:7c:c5:cd:85","rssi":"-91","ch":"9"}]
160         public static DataTable ToDataTableTwo(string json)
161         {
162             DataTable dataTable = new DataTable();  //实例化
163             DataTable result;
164             try
165             {
166                 List<Dictionary<string, object>> arrayList = JsonHelper.JSONToObject<List<Dictionary<string, object>>>(json);
167 
168                 if (arrayList != null && arrayList.Count > 0)
169                 {
170                     foreach (Dictionary<string, object> dictionary in arrayList)
171                     {
172                         if (dictionary.Keys.Count == 0)
173                         {
174                             result = dataTable;
175                             return result;
176                         }
177 
178                         //Columns
179                         if (dataTable.Columns.Count == 0)
180                         {
181                             foreach (var current in dictionary)
182                             {
183                                 if (current.Value != null)
184                                 {
185                                     dataTable.Columns.Add(current.Key, current.Value.GetType());
186                                 }
187                                 else
188                                 {
189                                     dataTable.Columns.Add(current.Key);
190                                 }
191                             }
192                         }
193 
194                         //Rows
195                         DataRow dataRow = dataTable.NewRow();
196 
197                         foreach (string current in dictionary.Keys)
198                         {
199                             if (dictionary[current] != null)
200                             {
201                                 dataRow[current] = dictionary[current];
202                             }
203                         }
204 
205                         dataTable.Rows.Add(dataRow); //循环添加行到DataTable中
206                     }
207                 }
208             }
209             catch (Exception ex)
210             {
211                 throw ex;
212             }
213 
214             result = dataTable;
215             return result;
216         }
217         #endregion

 

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