Update mongodb

Src/Asp.NetCore2/MongoDb.Ado.data/MongoDbDataAdapter.cs

@@ -78,30 +78,38 @@ namespace MongoDb.Ado.data
             var rows = dt.Rows;
             using (DbDataReader dr = command.ExecuteReader())
             {
-                for (int i = 0; i < dr.FieldCount; i++)
+                if (dr.Read())
                 {
-                    string name = dr.GetName(i).Trim();
+                    for (int i = 0; i < dr.FieldCount; i++)
-                    if (!columns.Contains(name))
-                        columns.Add(new DataColumn(name, dr.GetFieldType(i)));
-                    else
                     {
-                        columns.Add(new DataColumn(name + i, dr.GetFieldType(i)));
+                        string name = dr.GetName(i).Trim();
+                        if (!columns.Contains(name))
+                            columns.Add(new DataColumn(name, dr.GetFieldType(i)));
+                        else
+                        {
+                            columns.Add(new DataColumn(name + i, dr.GetFieldType(i)));
+                        }
                     }
-                }
+                    AddRow(dt, columns, dr);
-
+                    while (dr.Read())
-                while (dr.Read())
-                {
-                    DataRow daRow = dt.NewRow();
-                    for (int i = 0; i < columns.Count; i++)
                     {
-                        daRow[columns[i].ColumnName] = dr.GetValue(i);
+                        AddRow(dt, columns, dr);
                     }
-                    dt.Rows.Add(daRow);
                 }
             }
             dt.AcceptChanges();
         }
 
+        private static void AddRow(DataTable dt, DataColumnCollection columns, DbDataReader dr)
+        {
+            DataRow daRow = dt.NewRow();
+            for (int i = 0; i < columns.Count; i++)
+            {
+                daRow[columns[i].ColumnName] = dr.GetValue(i);
+            }
+            dt.Rows.Add(daRow);
+        }
+
         /// <summary>
         /// Fill
         /// </summary>
@@ -112,13 +120,13 @@ namespace MongoDb.Ado.data
             {
                 ds = new DataSet();
             }
+            var dt = new DataTable();
             using (DbDataReader dr = command.ExecuteReader())
             {
-                do
+                var columns = dt.Columns;
+                var rows = dt.Rows;
+                if (dr.Read())
                 {
-                    var dt = new DataTable();
-                    var columns = dt.Columns;
-                    var rows = dt.Rows;
                     for (int i = 0; i < dr.FieldCount; i++)
                     {
                         string name = dr.GetName(i).Trim();
@@ -129,19 +137,13 @@ namespace MongoDb.Ado.data
                             columns.Add(new DataColumn(name + i, dr.GetFieldType(i)));
                         }
                     }
-
+                    AddRow(dt, columns, dr);
                     while (dr.Read())
                     {
-                        DataRow daRow = dt.NewRow();
+                        AddRow(dt, columns, dr);
-                        for (int i = 0; i < columns.Count; i++)
-                        {
-                            daRow[columns[i].ColumnName] = dr.GetValue(i);
-                        }
-                        dt.Rows.Add(daRow);
                     }
-                    dt.AcceptChanges();
+                }
-                    ds.Tables.Add(dt);
+                ds.Tables.Add(dt);
-                } while (dr.NextResult());
             }
         }
 

Src/Asp.NetCore2/MongoDb.Ado.data/MongoDbDataReader.cs

@@ -13,36 +13,9 @@ namespace MongoDb.Ado.data
     {
         private readonly IEnumerator<BsonDocument> _enumerator;
         private BsonDocument _current;
-        private List<string> _fieldNames;
-        private List<Type> _fieldTypes;
         public MongoDbBsonDocumentDataReader(IEnumerable<BsonDocument> documents)
         {
-            var docList = documents.Take(1).ToList();
+            _enumerator = documents.GetEnumerator();
-            _enumerator = docList.GetEnumerator();
-            if (docList.Any()==true)
-            {
-                _fieldNames = docList.SelectMany(d => d.Names).Distinct(StringComparer.OrdinalIgnoreCase).ToList();
-                _fieldTypes = new List<Type>(); 
-                foreach (var fieldName in _fieldNames)
-                {
-                    Type fieldType = typeof(object); // 默认类型
-
-                    foreach (var doc in docList)
-                    {
-                        if (doc.TryGetValue(fieldName, out var value) && value != BsonNull.Value)
-                        {
-                            fieldType = BsonTypeMapper.MapToDotNetValue(value)?.GetType() ?? typeof(object);
-                        }
-                        break;
-                    }
-                    _fieldTypes.Add(fieldType);
-                }
-            }
-            else
-            {
-                _fieldNames = new List<string>();
-                _fieldTypes = new List<Type>();
-            } 
         }
 
         public override bool Read()
@@ -55,7 +28,7 @@ namespace MongoDb.Ado.data
             return false;
         }
 
-        public override int FieldCount => _fieldNames.Count;
+        public override int FieldCount => _current?.Count()??0;
 
         public override int Depth => throw new NotImplementedException();
 
@@ -77,7 +50,12 @@ namespace MongoDb.Ado.data
         public override DateTime GetDateTime(int ordinal) => (DateTime)GetValue(ordinal);
         public override decimal GetDecimal(int ordinal) => (decimal)GetValue(ordinal);
         public override double GetDouble(int ordinal) => (double)GetValue(ordinal);
-        public override Type GetFieldType(int ordinal) => _fieldTypes[ordinal] ?? typeof(object);
+        public override Type GetFieldType(int ordinal)
+        {
+            var obj = GetValue(ordinal);
+            if (obj == null) return typeof(object);
+            return obj.GetType();
+        }
         public override float GetFloat(int ordinal) => (float)GetValue(ordinal);
         public override Guid GetGuid(int ordinal) => (Guid)GetValue(ordinal);
         public override short GetInt16(int ordinal) => (short)GetValue(ordinal);
@@ -102,9 +80,18 @@ namespace MongoDb.Ado.data
 
         public override string GetName(int ordinal)
         {
-            if (ordinal < 0 || ordinal >= _fieldNames.Count)
+            if (_current == null)
+                throw new InvalidOperationException("No current document.");
+
+            // 获取当前文档的字段元素列表（Elements）
+            var elements = _current.Elements.ToList();
+
+            // 确保 ordinal 是有效的索引
+            if (ordinal < 0 || ordinal >= elements.Count)
                 throw new IndexOutOfRangeException($"Invalid ordinal: {ordinal}");
-            return _fieldNames[ordinal];
+
+            // 返回对应索引的字段名
+            return elements[ordinal].Name;
         }
 
         public override int GetOrdinal(string name)

Src/Asp.NetCore2/MongoDbTest/AdoTest.cs

@@ -119,6 +119,7 @@ namespace MongoDbTest
 
         private static void DataTableTest()
         {
+            //datatable
             {
                 var connection = new MongoDbConnection(DbHelper.SqlSugarConnectionString);
                 connection.Open();
@@ -130,6 +131,18 @@ namespace MongoDbTest
                 mongoDbDataAdapter.Fill(dt);
                 connection.Close();
             }
+            //dataset
+            {
+                var connection = new MongoDbConnection(DbHelper.SqlSugarConnectionString);
+                connection.Open();
+                ////SELECT *  FROM b ORDER BY age DESC OFFSET 1 ROWS FETCH NEXT 2 ROWS ONLY; 
+                MongoDbCommand mongoDbCommand = new MongoDbCommand(" aggregate b [\r\n  { \"$sort\": { \"age\": -1 } },\r\n  { \"$skip\": 1 },\r\n  { \"$limit\": 2 }\r\n] ]", connection);
+                MongoDbDataAdapter mongoDbDataAdapter = new MongoDbDataAdapter();
+                mongoDbDataAdapter.SelectCommand = mongoDbCommand;
+                DataSet ds = new DataSet();
+                mongoDbDataAdapter.Fill(ds);
+                connection.Close();
+            }
         }
         private static void ExecuteScalarTest()
         {