from:http://www.cnblogs.com/3echo/archive/2006/08/16/478094.html
1 /// <summary>
2 /// 得到要素类某字段的唯一值 3 /// </summary> 4 /// <param name="pFeatureClass"> 要素类 </param> 5 /// <param name="strFld"> 指定要得到唯一值的字段 </param> 6 /// <returns> 唯一值字符数据 </returns> 7 List< string> GetUniqueValue(IFeatureClass pFeatureClass, string strFld) 8 { 9 List< string> lst = new List< string>(); 10 // 得到IFeatureCursor游标 11 IFeatureCursor pCursor = pFeatureClass.Search( null, false); 12 13 // coClass对象实例生成 14 IDataStatistics pData = new DataStatisticsClass(); 15 pData.Field = strFld; 16 pData.Cursor = pCursor as ICursor; 17 18 // 枚举唯一值 19 IEnumerator pEnumVar = pData.UniqueValues; 20 21 // 记录总数 22 int RecordCount = pData.UniqueValueCount; 23 24 // 字符数组 25 pEnumVar.Reset(); 26 27 while (pEnumVar.MoveNext()) 28 { 29 lst.Add(pEnumVar.Current.ToString()); 30 } 31 32 return lst; 33 }