Added new configuration options, exception throw for sheet name too long, bugfix of invalid cell index mistaken for valid

src/MiniExcel/ExcelFactory.cs

@@ -6,7 +6,7 @@
     using System;
     using System.IO;
 
-    internal class ExcelReaderFactory
+    internal static class ExcelReaderFactory
     {
         internal static IExcelReader GetProvider(Stream stream, ExcelType excelType, IConfiguration configuration)
         {
@@ -17,19 +17,21 @@ internal static IExcelReader GetProvider(Stream stream, ExcelType excelType, ICo
                 case ExcelType.XLSX:
                     return new ExcelOpenXmlSheetReader(stream, configuration);
                 default:
-                    throw new NotSupportedException($"Please Issue for me");
+                    throw new NotSupportedException("Please Issue for me");
             }
         }
     }
 
-    internal class ExcelWriterFactory
+    internal static class ExcelWriterFactory
     {
         internal static IExcelWriter GetProvider(Stream stream, object value, string sheetName, ExcelType excelType, IConfiguration configuration, bool printHeader)
         {
             if (string.IsNullOrEmpty(sheetName))
-                throw new InvalidDataException("Sheet name can not be empty or null");
+                throw new ArgumentException("Sheet names can not be empty or null", nameof(sheetName));
+            if (sheetName.Length > 31 && excelType == ExcelType.XLSX)
+                throw new ArgumentException("Sheet names must be less than 31 characters", nameof(sheetName));
             if (excelType == ExcelType.UNKNOWN)
-                throw new InvalidDataException("Please specify excelType");
+                throw new ArgumentException("Excel type cannot be ExcelType.UNKNOWN", nameof(excelType));
 
             switch (excelType)
             {
@@ -38,12 +40,12 @@ internal static IExcelWriter GetProvider(Stream stream, object value, string she
                 case ExcelType.XLSX:
                     return new ExcelOpenXmlSheetWriter(stream, value, sheetName, configuration, printHeader);
                 default:
-                    throw new NotSupportedException($"Please Issue for me");
+                    throw new NotSupportedException($"The {excelType} Excel format is not supported");
             }
         }
     }
 
-    internal class ExcelTemplateFactory
+    internal static class ExcelTemplateFactory
     {
         internal static IExcelTemplateAsync GetProvider(Stream stream, IConfiguration configuration, ExcelType excelType = ExcelType.XLSX)
         {
@@ -53,7 +55,7 @@ internal static IExcelTemplateAsync GetProvider(Stream stream, IConfiguration co
                     var valueExtractor = new InputValueExtractor();
                     return new ExcelOpenXmlTemplate(stream, configuration, valueExtractor);
                 default:
-                    throw new NotSupportedException($"Please Issue for me");
+                    throw new NotSupportedException("Please Issue for me");
             }
         }
     }

src/MiniExcel/MiniExcel.cs

@@ -50,10 +50,9 @@ public static int Insert(string path, object value, string sheetName = "Sheet1",
         public static int Insert(this Stream stream, object value, string sheetName = "Sheet1", ExcelType excelType = ExcelType.XLSX, IConfiguration configuration = null, bool printHeader = true, bool overwriteSheet = false)
         {
             stream.Seek(0, SeekOrigin.End);
-            // reuse code
             if (excelType == ExcelType.CSV)
             {
-                var newValue = value is IEnumerable || value is IDataReader ? value : new[]{value}.AsEnumerable();
+                var newValue = value is IEnumerable || value is IDataReader ? value : new[]{value};
                 return ExcelWriterFactory.GetProvider(stream, newValue, sheetName, excelType, configuration, false).Insert(overwriteSheet);
             }
             else
@@ -88,9 +87,7 @@ public static int[] SaveAs(this Stream stream, object value, bool printHeader =
         {
             using (var excelReader = ExcelReaderFactory.GetProvider(stream, ExcelTypeHelper.GetExcelType(stream, excelType), configuration))
                 foreach (var item in excelReader.Query<T>(sheetName, startCell))
-                {
                     yield return item;
-                }
         }
         public static IEnumerable<dynamic> Query(string path, bool useHeaderRow = false, string sheetName = null, ExcelType excelType = ExcelType.UNKNOWN, string startCell = "A1", IConfiguration configuration = null)
         {

src/MiniExcel/OpenXml/ExcelOpenXmlSheetWriter.DefaultOpenXml.cs

@@ -308,19 +308,17 @@ private string GetFileValue(int rowIndex, int cellIndex, object value)
         private Tuple<string, string, string> GetDateTimeValue(DateTime value, ExcelColumnInfo columnInfo)
         {
             string cellValue = null;
-            if (!_configuration.Culture.Equals(CultureInfo.InvariantCulture))
+            if (!ReferenceEquals(_configuration.Culture, CultureInfo.InvariantCulture))
             {
                 cellValue = value.ToString(_configuration.Culture);
                 return Tuple.Create("2", "str", cellValue);
             }
 
             var oaDate = CorrectDateTimeValue(value);
             cellValue = oaDate.ToString(CultureInfo.InvariantCulture);
-
-            if (columnInfo?.ExcelFormat != null)
-                return Tuple.Create(columnInfo.ExcelFormatId.ToString(), (string)null, cellValue);
-
-            return Tuple.Create("3", (string)null, cellValue);
+            var format = columnInfo?.ExcelFormat != null ? columnInfo.ExcelFormatId.ToString() : "3";
+
+            return Tuple.Create(format, (string)null, cellValue);
         }
 
         private static double CorrectDateTimeValue(DateTime value)

src/MiniExcel/OpenXml/OpenXmlConfiguration.cs

@@ -14,6 +14,8 @@ public class OpenXmlConfiguration : Configuration
         public bool IgnoreTemplateParameterMissing { get; set; } = true;
         public bool EnableWriteNullValueCell { get; set; } = true;
         public bool WriteEmptyStringAsNull { get; set; } = false;
+        public bool TrimColumnNames { get; set; } = true;
+        public bool IgnoreEmptyRows { get; set; } = false;
         public bool EnableSharedStringCache { get; set; } = true;
         public long SharedStringCacheSize { get; set; } = 5 * 1024 * 1024;
         public DynamicExcelSheet[] DynamicSheets { get; set; }

src/MiniExcel/Utils/ColumnHelper.cs

@@ -1,17 +1,19 @@
-namespace MiniExcelLibs.Utils
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.IO;
+
+namespace MiniExcelLibs.Utils
 {
-    using System.Collections.Concurrent;
-    using System.Collections.Generic;
-    using System.IO;
 
     // For Row/Column Index
-    internal static partial class ColumnHelper
+    internal static class ColumnHelper
     {
         private const int GENERAL_COLUMN_INDEX = 255;
         private const int MAX_COLUMN_INDEX = 16383;
         private static int _IntMappingAlphabetCount = 0;
         private static readonly ConcurrentDictionary<int, string> _IntMappingAlphabet = new ConcurrentDictionary<int, string>();
         private static readonly ConcurrentDictionary<string, int> _AlphabetMappingInt = new ConcurrentDictionary<string, int>();
+
         static ColumnHelper()
         {
             _IntMappingAlphabetCount = _IntMappingAlphabet.Count;
@@ -21,9 +23,8 @@ static ColumnHelper()
         public static string GetAlphabetColumnName(int columnIndex)
         {
             CheckAndSetMaxColumnIndex(columnIndex);
-            if (_IntMappingAlphabet.TryGetValue(columnIndex, out var value))
-                return value;
-            throw new KeyNotFoundException();
+            return _IntMappingAlphabet.TryGetValue(columnIndex, out var value) ? value
+                : throw new KeyNotFoundException();
         }
 
         public static int GetColumnIndex(string columnName)
@@ -35,23 +36,23 @@ public static int GetColumnIndex(string columnName)
 
         private static void CheckAndSetMaxColumnIndex(int columnIndex)
         {
-            if (columnIndex >= _IntMappingAlphabetCount)
+            if (columnIndex < _IntMappingAlphabetCount)
+                return;
+            if (columnIndex > MAX_COLUMN_INDEX)
+                throw new InvalidDataException($"ColumnIndex {columnIndex} over excel vaild max index.");
+
+            for (int i = _IntMappingAlphabet.Count; i <= columnIndex; i++)
             {
-                if (columnIndex > MAX_COLUMN_INDEX)
-                    throw new InvalidDataException($"ColumnIndex {columnIndex} over excel vaild max index.");
-                for (int i = _IntMappingAlphabet.Count; i <= columnIndex; i++)
-                {
-                    _IntMappingAlphabet.AddOrUpdate(i, IntToLetters(i), (a, b) => IntToLetters(i));
-                    _AlphabetMappingInt.AddOrUpdate(IntToLetters(i), i, (a, b) => i);
-                }
-                _IntMappingAlphabetCount = _IntMappingAlphabet.Count;
+                _IntMappingAlphabet.AddOrUpdate(i, IntToLetters(i), (a, b) => IntToLetters(i));
+                _AlphabetMappingInt.AddOrUpdate(IntToLetters(i), i, (a, b) => i);
             }
+            _IntMappingAlphabetCount = _IntMappingAlphabet.Count;
         }
 
         internal static string IntToLetters(int value)
         {
-            value = value + 1;
-            string result = string.Empty;
+            value++;
+            var result = string.Empty;
             while (--value >= 0)
             {
                 result = (char)('A' + value % 26) + result;
@@ -60,5 +61,4 @@ internal static string IntToLetters(int value)
             return result;
         }
     }
-
 }