【转】获取图层字段的唯一值集合（ArcEngine）

 原文：http://www.3snews.net/html/93/7693-10766.html

 

可以通过IDataStatistics来实现的. 下面是通过IQueryDef 来实现.

 

public ArrayList GetUVByQueryDef(IFeatureLayer pFeatureLayer, string strField)
        {

            IDataset pDataset = (IDataset)pFeatureLayer.FeatureClass;
            IFeatureWorkspace pFeatureWorkspace = (IFeatureWorkspace)pDataset.Workspace;
            IQueryDef pQueryDef = pFeatureWorkspace.CreateQueryDef();
            pQueryDef.Tables = pDataset.Name;
            pQueryDef.SubFields = "DISTINCT("+strField + ")";
            ICursor pCursor = pQueryDef.Evaluate();

            IRow pRow = pCursor.NextRow();
            ArrayList uvList = new ArrayList();
            while (pRow != null)
            {
                object pObj = pRow.get_Value(0);
                uvList.Add(pObj.ToString());
                pRow = pCursor.NextRow();
            }
            return uvList;
        }