diff --git a/drafts/【MiniExcel】AutoFillCenterEmptyRowOrCellLogic.linq b/drafts/【MiniExcel】AutoFillCenterEmptyRowOrCellLogic.linq
deleted file mode 100644
index 3dfebaa..0000000
--- a/drafts/【MiniExcel】AutoFillCenterEmptyRowOrCellLogic.linq
+++ /dev/null
@@ -1,145 +0,0 @@
-<Query Kind="Program">
-  <NuGetReference>AngleSharp</NuGetReference>
-  <NuGetReference>Dapper</NuGetReference>
-  <NuGetReference>DocumentFormat.OpenXml</NuGetReference>
-  <NuGetReference>Newtonsoft.Json</NuGetReference>
-  <NuGetReference>System.Data.SqlClient</NuGetReference>
-  <Namespace>Dapper</Namespace>
-  <Namespace>Newtonsoft.Json</Namespace>
-  <Namespace>System.Data.SqlClient</Namespace>
-  <Namespace>System.IO.Compression</Namespace>
-  <Namespace>System.Net.Http</Namespace>
-  <Namespace>System.Threading.Tasks</Namespace>
-</Query>
-
-void Main()
-{
-	var source = new Dictionary<int, Dictionary<int, object>>()
-	{
-		{0,new Dictionary<int,object>(){{0,0},{3,3}}},
-		{3,new Dictionary<int,object>(){{2,2}}},
-	};
-	Console.WriteLine(JsonConvert.SerializeObject(source, Newtonsoft.Json.Formatting.Indented));
-	var rows = GetRows(@"D:\git\MiniExcel\samples\xlsx\TestCenterEmptyRow\TestCenterEmptyRow.xlsx").ToList();
-	Console.WriteLine(rows);
-}
-
-private static string ConvertToString(ZipArchiveEntry entry)
-{
-	if (entry == null)
-		return null;
-	using (var eStream = entry.Open())
-	using (var reader = new StreamReader(eStream))
-		return reader.ReadToEnd();
-}
-
-internal static class ExcelXName
-{
-	internal readonly static XNamespace ExcelNamespace = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main");
-	internal readonly static XNamespace ExcelRelationshipsNamepace = XNamespace.Get("http://schemas.openxmlformats.org/officeDocument/2006/relationships");
-	internal readonly static XName Row;
-	internal readonly static XName R;
-	internal readonly static XName V;
-	internal readonly static XName T;
-	internal readonly static XName C;
-	internal readonly static XName Dimension;
-	static ExcelXName()
-	{
-		Row = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "row";
-		R = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "r";
-		V = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "v";
-		T = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "t";
-		C = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "c";
-		Dimension = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "dimension";
-	}
-}
-
-IEnumerable<IEnumerable<object>> GetRows(string path)
-{
-	using (FileStream stream = new FileStream(path, FileMode.Open))
-	using (ZipArchive archive = new ZipArchive(stream, ZipArchiveMode.Read, false, UTF8Encoding.UTF8))
-	{
-		var firstSheetEntry = archive.Entries.First(w => w.FullName.StartsWith("xl/worksheets/", StringComparison.OrdinalIgnoreCase));
-		var xml = ConvertToString(firstSheetEntry);
-		var xl = XElement.Parse(xml);
-
-		var maxRowIndex = 3;
-		var maxColumnIndex = 3;
-
-		// first get sheet row count & column count
-
-		var rowIndex = 0;
-		foreach (var row in xl.Descendants(ExcelXName.Row))
-		{
-			{
-				var r = row.Attribute("r")?.Value?.ToString();
-
-				var rIndex = int.MinValue;
-				if (int.TryParse(r, out var _rowIndex))
-					rIndex = _rowIndex - 1; // The row attribute is 1 - based			
-			}
-
-
-			var cells = new List<object>(maxColumnIndex);
-
-			foreach (var cell in row.Descendants(ExcelXName.C))
-			{
-
-			}
-
-			yield return cells;
-		}
-	}
-}
-
-void Main2()
-{
-	{
-		var dic = new Dictionary<int, Dictionary<int, object>>() {
-			{0,new Dictionary<int,object>(){{0,0},{3,3}}},
-			{3,new Dictionary<int,object>(){{2,3}}},
-		};
-		Console.WriteLine(JsonConvert.SerializeObject(dic, Newtonsoft.Json.Formatting.Indented));
-
-		var maxRowIndex = 3;
-		var maxColumnIndex = 3;
-		for (int rowIndex = 0; rowIndex <= maxRowIndex; rowIndex++)
-		{
-			if (!dic.ContainsKey(rowIndex))
-			{
-				var d = new Dictionary<int, object>();
-				for (int columnIndex = 0; columnIndex <= maxColumnIndex; columnIndex++)
-				{
-					d.Add(columnIndex, null);
-				}
-				dic.Add(rowIndex, d);
-			}
-			else
-			{
-				var d = dic[rowIndex];
-				for (int columnIndex = 0; columnIndex <= maxColumnIndex; columnIndex++)
-				{
-					if (!d.ContainsKey(columnIndex))
-					{
-						d.Add(columnIndex, null);
-					}
-				}
-			}
-		}
-
-		Console.WriteLine(JsonConvert.SerializeObject(dic, Newtonsoft.Json.Formatting.Indented));
-	}
-	{
-		var dic = new Dictionary<int, Dictionary<int, object>>() {
-			{0,new Dictionary<int,object>(){{0,0},{1,null},{2,null},{3,3}}},
-			{1,new Dictionary<int,object>(){{0,null},{1,null},{2,null},{3,null}}},
-			{2,new Dictionary<int,object>(){{0,null},{1,null},{2,null},{3,null}}},
-			{3,new Dictionary<int,object>(){{0,null},{1,null},{2,2},{3,null}}},
-		};
-		//Console.WriteLine(dic);
-		var json = JsonConvert.SerializeObject(dic, Newtonsoft.Json.Formatting.Indented);
-		Console.WriteLine(json);
-	}
-}
-
-// You can define other methods, fields, classes and namespaces here
diff --git a/drafts/【MiniExcel】Reader Mode.linq b/drafts/【MiniExcel】Reader Mode.linq
new file mode 100644
index 0000000..28b932d
--- /dev/null
+++ b/drafts/【MiniExcel】Reader Mode.linq	
@@ -0,0 +1,350 @@
+<Query Kind="Program">
+  <NuGetReference>AngleSharp</NuGetReference>
+  <NuGetReference>Dapper</NuGetReference>
+  <NuGetReference>DocumentFormat.OpenXml</NuGetReference>
+  <NuGetReference>Newtonsoft.Json</NuGetReference>
+  <NuGetReference>System.Data.SqlClient</NuGetReference>
+  <Namespace>Dapper</Namespace>
+  <Namespace>Newtonsoft.Json</Namespace>
+  <Namespace>System.Data.SqlClient</Namespace>
+  <Namespace>System.Net.Http</Namespace>
+  <Namespace>System.Threading.Tasks</Namespace>
+  <Namespace>System.IO.Compression</Namespace>
+</Query>
+
+void Main()
+{
+	using (var reader = new XlsxEasyRowsValueReader(@"D:\git\MiniExcel\samples\xlsx\TestCenterEmptyRow\TestCenterEmptyRow.xlsx"))
+	{
+		while (reader.Read())
+		{
+			Console.WriteLine($"row : {reader.CurrentRowIndex}");
+			Console.Write("Cells : | ");
+			for (int i = 0; i < reader.FieldCount; i++)
+			{
+				var v = reader.GetValue(i);
+				Console.Write(v == null ? null : v);
+				Console.Write(" | ");
+			}
+			Console.WriteLine();
+		}
+	}
+}
+
+internal class Worksheet
+{
+	public int RowCount { get; set; }
+	public int FieldCount { get; set; }
+	public Dictionary<int, Dictionary<int, object>> Rows { get; set; }
+}
+
+// You can define other methods, fields, classes and namespaces here
+public class MiniExcel
+{
+	internal static Worksheet ConvertAsSheet(string path)
+	{
+		using (FileStream stream = new FileStream(path, FileMode.Open))
+		using (ZipArchive archive = new ZipArchive(stream, ZipArchiveMode.Read, false, UTF8Encoding.UTF8))
+		{
+			//sharedStrings must in memory cache
+			Dictionary<int, string> GetSharedStrings()
+			{
+				var sharedStringsEntry = archive.Entries.SingleOrDefault(w => w.FullName == "xl/sharedStrings.xml");
+				var xml = ConvertToString(sharedStringsEntry);
+				var xl = XElement.Parse(xml);
+				var ts = xl.Descendants(ExcelXName.T).Select((s, i) => new { i, v = s.Value?.ToString() })
+					.ToDictionary(s => s.i, s => s.v)
+				;
+				return ts;
+			}
+
+			var sharedStrings = GetSharedStrings();
+
+			//notice: for performance just read first one and no care the order
+			var rowIndexMaximum = int.MinValue;
+			var columnIndexMaximum = int.MinValue;
+
+
+
+			var datarows = new Dictionary<int, Dictionary<int, object>>();
+			var firstSheetEntry = archive.Entries.First(w => w.FullName.StartsWith("xl/worksheets/", StringComparison.OrdinalIgnoreCase));
+			{
+				var xml = ConvertToString(firstSheetEntry);
+				var xl = XElement.Parse(xml);
+
+				foreach (var row in xl.Descendants(ExcelXName.Row))
+				{
+					//
+					var datarow = new Dictionary<int, object>();
+					{
+						var r = row.Attribute("r")?.Value?.ToString();
+
+						var rowIndex = int.MinValue;
+						if (int.TryParse(r, out var _rowIndex))
+							rowIndex = _rowIndex - 1; // The row attribute is 1 - based				
+						rowIndexMaximum = Math.Max(rowIndexMaximum, rowIndex);
+
+						datarows.Add(rowIndex, datarow);
+					}
+
+					foreach (var cell in row.Descendants(ExcelXName.C))
+					{
+						var t = cell.Attribute("t")?.Value?.ToString();
+						var v = cell.Descendants(ExcelXName.V).SingleOrDefault()?.Value;
+						if (t == "s")
+						{
+							if (!string.IsNullOrEmpty(v))
+								v = sharedStrings[int.Parse(v)];
+						}
+
+						var r = cell.Attribute("r")?.Value?.ToString();
+						{
+							var cellIndex = GetColumnIndex(r) - 1;
+							columnIndexMaximum = Math.Max(columnIndexMaximum, cellIndex);
+
+							datarow.Add(cellIndex, v);
+						}
+					}
+				}
+			}
+
+			return new Worksheet { FieldCount=columnIndexMaximum+1,RowCount=rowIndexMaximum+1,Rows=datarows};
+		}
+	}
+
+	private static string ConvertToString(ZipArchiveEntry entry)
+	{
+		if (entry == null)
+			return null;
+		using (var eStream = entry.Open())
+		using (var reader = new StreamReader(eStream))
+			return reader.ReadToEnd();
+	}
+
+	/// <summary>X=CellLetter,Y=CellNumber,ex:A1=(1,1),B2=(2,2)</summary>
+	internal static void ConvertCellToXY(string cell,out int x,out int y)
+	{
+		x=GetColumnIndex(cell);
+		y=GetCellNumber(cell);
+	}
+
+	internal static int GetColumnIndex(string cell)
+	{
+		const string keys = " ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+		const int mode = 26;
+
+		var x = 0;
+		var cellLetter = GetCellLetter(cell);
+		//AA=27,ZZ=702
+		for (int i = 0; i < cellLetter.Length; i++)
+			x = x * mode + keys.IndexOf(cellLetter[i]);
+
+		return x;
+	}
+
+	internal static int GetCellNumber(string cell)
+	{
+		if (string.IsNullOrEmpty(cell))
+			throw new Exception("cell is null or empty");
+		string cellNumber = string.Empty;
+		for (int i = 0; i < cell.Length; i++)
+		{
+			if (Char.IsDigit(cell[i]))
+				cellNumber += cell[i];
+		}
+		return int.Parse(cellNumber);
+	}
+
+	internal static string GetCellLetter(string cell)
+	{
+		string GetCellLetter = string.Empty;
+		for (int i = 0; i < cell.Length; i++)
+		{
+			if (Char.IsLetter(cell[i]))
+				GetCellLetter += cell[i];
+		}
+		return GetCellLetter;
+	}
+}
+
+internal static class ExcelXName
+{
+	internal readonly static XNamespace ExcelNamespace = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main");
+	internal readonly static XNamespace ExcelRelationshipsNamepace = XNamespace.Get("http://schemas.openxmlformats.org/officeDocument/2006/relationships");
+	internal readonly static XName Row;
+	internal readonly static XName R;
+	internal readonly static XName V;
+	internal readonly static XName T;
+	internal readonly static XName C;
+	internal readonly static XName Dimension;
+	static ExcelXName()
+	{
+		Row = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "row";
+		R = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "r";
+		V = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "v";
+		T = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "t";
+		C = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "c";
+		Dimension = XNamespace.Get("http://schemas.openxmlformats.org/spreadsheetml/2006/main") + "dimension";
+	}
+}
+
+public class XlsxEasyRowsValueReader : IDataReader
+{
+	private static Worksheet[] _Sheets = new Worksheet[1];
+	private Dictionary<int, Dictionary<int, object>> _Rows {get{return _Sheets[0].Rows;}}
+
+	public XlsxEasyRowsValueReader(string filePath)
+	{
+ 		_Sheets[0] = MiniExcel.ConvertAsSheet(filePath);
+	}
+
+	public int RowCount {get{return _Sheets[0].RowCount;}}
+	public int FieldCount {get{return _Sheets[0].FieldCount;}}
+	public int Depth { get; private set; }
+	public int CurrentRowIndex { get { return Depth - 1; } }
+
+	public object this[int i] => GetValue(i);
+	public object this[string name] => GetValue(GetOrdinal(name));
+
+	public bool Read()
+	{
+		if (Depth == RowCount)
+			return false;
+		Depth++;
+		return true;
+	}
+
+	public string GetName(int i) => Helper.ConvertColumnName(i + 1);
+
+
+	public int GetOrdinal(string name)
+	{
+		//TODO
+		var keys = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray().ToList();
+		var dic = keys.ToDictionary(s => s, s => keys.IndexOf(s));
+		return dic[(name[0])];
+	}
+
+	public object GetValue(int i)
+	{
+		//if (CurrentRowIndex < 0)
+		//	throw new InvalidOperationException("Invalid attempt to read when no data is present.");
+		if (!_Rows.Keys.Contains(CurrentRowIndex))
+			return null;
+		if (_Rows[this.CurrentRowIndex].TryGetValue(i, out var v))
+			return v;
+		return null;
+	}
+
+	public int GetValues(object[] values)
+	{
+		return this.Depth;
+	}
+
+	//TODO: multiple sheets
+	public bool NextResult() => false;
+
+	public void Dispose() { }
+
+	public void Close() { }
+
+	public int RecordsAffected => throw new NotImplementedException();
+
+	bool IDataReader.IsClosed => this.RowCount - 1 == this.Depth;
+
+	public string GetString(int i) => (string)GetValue(i);
+
+	public bool GetBoolean(int i) => (bool)GetValue(i);
+
+	public byte GetByte(int i) => (byte)GetValue(i);
+
+	public long GetBytes(int i, long fieldOffset, byte[] buffer, int bufferoffset, int length) => throw new NotImplementedException();
+
+	public char GetChar(int i) => (char)GetValue(i);
+
+	public long GetChars(int i, long fieldoffset, char[] buffer, int bufferoffset, int length) => throw new NotImplementedException();
+
+	public IDataReader GetData(int i) => throw new NotImplementedException();
+
+	public string GetDataTypeName(int i) => throw new NotImplementedException();
+
+	public DateTime GetDateTime(int i) => (DateTime)GetValue(i);
+
+	public decimal GetDecimal(int i) => (decimal)GetValue(i);
+
+	public double GetDouble(int i) => (double)GetValue(i);
+
+	public Type GetFieldType(int i)
+	{
+		var v = GetValue(i);
+		return v == null ? typeof(string) : v.GetType();
+	}
+
+	public float GetFloat(int i) => (float)GetValue(i);
+
+	public Guid GetGuid(int i) => (Guid)GetValue(i);
+
+	public short GetInt16(int i) => (short)GetValue(i);
+
+	public int GetInt32(int i) => (int)GetValue(i);
+
+	public long GetInt64(int i) => (long)GetValue(i);
+
+	public DataTable GetSchemaTable()
+	{
+		var dataTable = new DataTable("SchemaTable");
+		dataTable.Locale = System.Globalization.CultureInfo.InvariantCulture;
+		dataTable.Columns.Add("ColumnName", typeof(string));
+		dataTable.Columns.Add("ColumnOrdinal", typeof(int));
+		for (int i = 0; i < this.FieldCount; i++)
+		{
+			dataTable.Rows.Add(this.GetName(i), i);
+		}
+		DataColumnCollection columns = dataTable.Columns;
+		foreach (DataColumn item in columns)
+		{
+			item.ReadOnly = true;
+		}
+		return dataTable;
+	}
+
+	public bool IsDBNull(int i) => GetValue(i) == null;
+
+}
+
+internal static class Helper
+{
+	public static TValue GetValueOrDefault<TKey, TValue>
+	(this IDictionary<TKey, TValue> dictionary,
+	 TKey key,
+	 TValue defaultValue)
+	{
+		TValue value;
+		return dictionary.TryGetValue(key, out value) ? value : defaultValue;
+	}
+
+	public static TValue GetValueOrDefault<TKey, TValue>
+		(this IDictionary<TKey, TValue> dictionary,
+		 TKey key,
+		 Func<TValue> defaultValueProvider)
+	{
+		TValue value;
+		return dictionary.TryGetValue(key, out value) ? value
+			 : defaultValueProvider();
+	}
+
+	internal static string ConvertColumnName(int x)
+	{
+		int dividend = x;
+		string columnName = String.Empty;
+		int modulo;
+
+		while (dividend > 0)
+		{
+			modulo = (dividend - 1) % 26;
+			columnName = Convert.ToChar(65 + modulo).ToString() + columnName;
+			dividend = (int)((dividend - modulo) / 26);
+		}
+		return columnName;
+	}
+}
\ No newline at end of file
diff --git a/drafts/【Reader】Basic Reader.linq b/drafts/【Reader】Basic Reader.linq
new file mode 100644
index 0000000..a2e9c8b
--- /dev/null
+++ b/drafts/【Reader】Basic Reader.linq	
@@ -0,0 +1,264 @@
+<Query Kind="Program">
+  <NuGetReference>AngleSharp</NuGetReference>
+  <NuGetReference>Dapper</NuGetReference>
+  <NuGetReference>DocumentFormat.OpenXml</NuGetReference>
+  <NuGetReference>Newtonsoft.Json</NuGetReference>
+  <NuGetReference>System.Data.SqlClient</NuGetReference>
+  <Namespace>Dapper</Namespace>
+  <Namespace>Newtonsoft.Json</Namespace>
+  <Namespace>System.Data.SqlClient</Namespace>
+  <Namespace>System.Net.Http</Namespace>
+  <Namespace>System.Threading.Tasks</Namespace>
+  <Namespace>Xunit</Namespace>
+</Query>
+
+#load "xunit"
+
+#region private::Tests
+
+[Fact]
+void Test_NullRow()
+{
+	using (var reader = new XlsxEasyRowsValueReader(null))
+	{
+		Action testCode = () => { var v = reader[0]; };
+		var ex = Record.Exception(testCode);
+		Console.WriteLine();
+
+		Assert.NotNull(ex);
+		Assert.IsType<InvalidOperationException>(ex);
+	}
+}
+
+[Fact]
+void Test_ReaderGetName()
+{
+	using (var reader = new XlsxEasyRowsValueReader(null))
+	{
+		Assert.Equal("A", reader.GetName(0));
+		Assert.Equal("B", reader.GetName(1));
+		Assert.Equal("BD", reader.GetName(55));
+	}
+}
+
+[Fact]
+void Test_ReaderGetOriginal()
+{
+	using (var reader = new XlsxEasyRowsValueReader(null))
+	{
+		Assert.Equal(0, reader.GetOrdinal("A"));
+		//Assert.Equal("B", reader.GetName(1));
+		//Assert.Equal("BD", reader.GetName(55));
+	}
+}
+
+#endregion
+
+void Main()
+{
+	//RunTests();  // Call RunTests() or press Alt+Shift+T to initiate testing.
+
+	Console.WriteLine("========");
+	using (var reader = new XlsxEasyRowsValueReader(null))
+	{
+		var st = reader.GetSchemaTable();
+		Console.WriteLine(st);
+		//todo
+		var dt = new DataTable();
+		dt.Load(reader);
+	}
+
+	Console.WriteLine("========");
+	using (var reader = new XlsxEasyRowsValueReader(null))
+	{
+		while (reader.Read())
+		{
+			Console.WriteLine($"row : {reader.CurrentRowIndex}");
+			Console.Write("Cells : | ");
+			for (int i = 0; i < reader.FieldCount; i++)
+			{
+				var v = reader.GetValue(i);
+				Console.Write(v == null ? null : v);
+				Console.Write(" | ");
+			}
+			Console.WriteLine();
+		}
+	}
+
+	Console.WriteLine("========");
+	using (var reader = new XlsxEasyRowsValueReader(null))
+	{
+		for (int i = 0; i < reader.FieldCount; i++)
+		{
+			var name = reader.GetName(i);
+			Console.Write($" | name : {name}");
+			//var ordinal = reader.GetOrdinal(name);
+			//Console.Write($" | ordinal : {ordinal}");
+			Console.WriteLine();
+		}
+	}
+}
+
+
+
+public class XlsxEasyRowsValueReader : IDataReader
+{
+	private static Dictionary<int, Dictionary<int, object>> _Rows { get; set; } = new Dictionary<int, Dictionary<int, object>>() {
+		{0,new Dictionary<int,object>(){{0,0},{3,3}}},
+		{3,new Dictionary<int,object>(){{2,2}}},
+	};
+	
+	public XlsxEasyRowsValueReader(string filePath)
+	{
+		
+	}
+
+	public int RowCount { get; set; } = 4;
+	public int FieldCount { get; set; } = 4;
+	public int Depth { get; private set; }
+	public int CurrentRowIndex { get { return Depth - 1; } }
+
+	public object this[int i] => GetValue(i);
+	public object this[string name] => GetValue(GetOrdinal(name));
+
+	public bool Read()
+	{
+		if (Depth == RowCount)
+			return false;
+		Depth++;
+		return true;
+	}
+
+	public string GetName(int i) => Helper.ConvertColumnName(i + 1);
+
+
+	public int GetOrdinal(string name)
+	{
+		//TODO
+		var keys = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray().ToList();
+		var dic = keys.ToDictionary(s => s, s => keys.IndexOf(s));
+		return dic[(name[0])];
+	}
+
+	public object GetValue(int i)
+	{
+		//if (CurrentRowIndex < 0)
+		//	throw new InvalidOperationException("Invalid attempt to read when no data is present.");
+		if (!_Rows.Keys.Contains(CurrentRowIndex))
+			return null;
+		if (_Rows[this.CurrentRowIndex].TryGetValue(i, out var v))
+			return v;
+		return null;
+	}
+
+	public int GetValues(object[] values) {
+		return this.Depth;
+	}
+
+	//TODO: multiple sheets
+	public bool NextResult() => false;
+
+	public void Dispose() { }
+
+	public void Close() { }
+
+	public int RecordsAffected => throw new NotImplementedException();
+
+	bool IDataReader.IsClosed => this.RowCount - 1 == this.Depth;
+
+	public string GetString(int i) => (string)GetValue(i);
+
+	public bool GetBoolean(int i) => (bool)GetValue(i);
+
+	public byte GetByte(int i) => (byte)GetValue(i);
+
+	public long GetBytes(int i, long fieldOffset, byte[] buffer, int bufferoffset, int length) => throw new NotImplementedException();
+
+	public char GetChar(int i) => (char)GetValue(i);
+
+	public long GetChars(int i, long fieldoffset, char[] buffer, int bufferoffset, int length) => throw new NotImplementedException();
+
+	public IDataReader GetData(int i) => throw new NotImplementedException();
+
+	public string GetDataTypeName(int i) => throw new NotImplementedException();
+
+	public DateTime GetDateTime(int i) => (DateTime)GetValue(i);
+
+	public decimal GetDecimal(int i) => (decimal)GetValue(i);
+
+	public double GetDouble(int i) => (double)GetValue(i);
+
+	public Type GetFieldType(int i)
+	{
+		var v = GetValue(i);
+		return v==null ? typeof(string) : v.GetType();
+	}
+
+	public float GetFloat(int i) => (float)GetValue(i);
+
+	public Guid GetGuid(int i) => (Guid)GetValue(i);
+
+	public short GetInt16(int i) => (short)GetValue(i);
+
+	public int GetInt32(int i) => (int)GetValue(i);
+
+	public long GetInt64(int i) => (long)GetValue(i);
+
+	public DataTable GetSchemaTable()
+	{
+		var dataTable = new DataTable("SchemaTable");
+		dataTable.Locale = System.Globalization.CultureInfo.InvariantCulture;
+		dataTable.Columns.Add("ColumnName", typeof(string));
+		dataTable.Columns.Add("ColumnOrdinal", typeof(int));
+		for (int i = 0; i < this.FieldCount; i++)
+		{
+			dataTable.Rows.Add(this.GetName(i), i);
+		}
+		DataColumnCollection columns = dataTable.Columns;
+		foreach (DataColumn item in columns)
+		{
+			item.ReadOnly = true;
+		}
+		return dataTable;
+	}
+
+	public bool IsDBNull(int i) => GetValue(i) == null;
+	
+}
+
+internal static class Helper
+{
+	public static TValue GetValueOrDefault<TKey, TValue>
+	(this IDictionary<TKey, TValue> dictionary,
+	 TKey key,
+	 TValue defaultValue)
+	{
+		TValue value;
+		return dictionary.TryGetValue(key, out value) ? value : defaultValue;
+	}
+
+	public static TValue GetValueOrDefault<TKey, TValue>
+		(this IDictionary<TKey, TValue> dictionary,
+		 TKey key,
+		 Func<TValue> defaultValueProvider)
+	{
+		TValue value;
+		return dictionary.TryGetValue(key, out value) ? value
+			 : defaultValueProvider();
+	}
+
+	internal static string ConvertColumnName(int x)
+	{
+		int dividend = x;
+		string columnName = String.Empty;
+		int modulo;
+
+		while (dividend > 0)
+		{
+			modulo = (dividend - 1) % 26;
+			columnName = Convert.ToChar(65 + modulo).ToString() + columnName;
+			dividend = (int)((dividend - modulo) / 26);
+		}
+		return columnName;
+	}
+}
diff --git a/drafts/【SqlConnection】Trace Reader Mode.linq b/drafts/【SqlConnection】Trace Reader Mode.linq
new file mode 100644
index 0000000..d574f30
--- /dev/null
+++ b/drafts/【SqlConnection】Trace Reader Mode.linq	
@@ -0,0 +1,39 @@
+<Query Kind="Program">
+  <Connection>
+    <ID>2a2e3c0b-0e23-4992-bf19-66db2739e377</ID>
+    <Persist>true</Persist>
+    <Server>(localdb)\mssqllocaldb</Server>
+    <Database>Northwind</Database>
+  </Connection>
+  <NuGetReference>AngleSharp</NuGetReference>
+  <NuGetReference>Dapper</NuGetReference>
+  <NuGetReference>DocumentFormat.OpenXml</NuGetReference>
+  <NuGetReference>Newtonsoft.Json</NuGetReference>
+  <NuGetReference>System.Data.SqlClient</NuGetReference>
+  <Namespace>Dapper</Namespace>
+  <Namespace>Newtonsoft.Json</Namespace>
+  <Namespace>System.Data.SqlClient</Namespace>
+  <Namespace>System.Net.Http</Namespace>
+  <Namespace>System.Threading.Tasks</Namespace>
+</Query>
+
+void Main()
+{
+	using (var cn = (SqlConnection)this.Connection)
+	{
+		cn.Open();
+		using(var cmd = cn.CreateCommand()){
+			cmd.CommandText="select 1 id";
+			using(var reader = cmd.ExecuteReader()){
+				var name = reader.GetName(0);
+				Console.WriteLine(name);
+				var dt = reader.GetSchemaTable();
+				Console.WriteLine(dt);
+				var v = reader.GetValue(0);
+				var vs = reader.GetValues(null);
+			}
+		}
+	}
+}
+
+// You can define other methods, fields, classes and namespaces here