Add ExcelFileType to expose constants about different supported file …

…formats.

source/Sylvan.Data.Excel/ExcelFileType.cs

@@ -0,0 +1,225 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+namespace Sylvan.Data.Excel;
+
+/// <summary>
+/// Exposes information about the supported Excel file types.
+/// </summary>
+public sealed class ExcelFileType
+{
+ /// <summary>
+ /// The file extension for .xls files.
+ /// </summary>
+ public const string ExcelFileExtension = ".xls";
+
+ /// <summary>
+ /// The content type for .xls files.
+ /// </summary>
+ public const string ExcelContentType = "application/vnd.ms-excel";
+
+ /// <summary>
+ /// The file extension for .xlsx files.
+ /// </summary>
+ public const string ExcelXmlFileExtension = ".xlsx";
+
+ /// <summary>
+ /// The content type for .xlsx files.
+ /// </summary>
+ public const string ExcelXmlContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
+
+ /// <summary>
+ /// The file extension for .xlsm files.
+ /// </summary>
+ public const string ExcelXmlMacroEnabledFileExtension = ".xlsm";
+
+ /// <summary>
+ /// The content type for .xlsx files.
+ /// </summary>
+ public const string ExcelXmlMacroEnabledContentType = "application/vnd.ms-excel.sheet.macroEnabled.12";
+
+ /// <summary>
+ /// The file extension for .xlsb files.
+ /// </summary>
+ public const string ExcelBinaryFileExtension = ".xlsb";
+
+ /// <summary>
+ /// The content type for .xlsx files.
+ /// </summary>
+ public const string ExcelBinaryContentType = "application/vnd.ms-excel.sheet.binary.macroEnabled.12";
+
+
+ /// <summary>
+ /// The .xls file type.
+ /// </summary>
+ public static readonly ExcelFileType Excel =
+ new(ExcelFileExtension,
+ ExcelContentType,
+ ExcelWorkbookType.Excel
+ );
+
+ /// <summary>
+ /// The .xlsx file type.
+ /// </summary>
+ public static readonly ExcelFileType ExcelXml =
+ new(
+ ExcelXmlFileExtension,
+ ExcelXmlContentType,
+ ExcelWorkbookType.ExcelXml
+ );
+
+ /// <summary>
+ /// The .xlsm file type.
+ /// </summary>
+ public static readonly ExcelFileType ExcelXmlMacroEnabled =
+ new(
+ ExcelXmlMacroEnabledFileExtension,
+ ExcelXmlMacroEnabledContentType,
+ ExcelWorkbookType.ExcelXml
+ );
+
+ /// <summary>
+ /// The .xlsb file type.
+ /// </summary>
+ public static readonly ExcelFileType ExcelBinary =
+ new(
+ ExcelBinaryFileExtension,
+ ExcelBinaryContentType,
+ ExcelWorkbookType.ExcelBinary
+ );
+
+ /// <summary>
+ /// Enumerates all the file types exposed by the Sylvan library.
+ /// </summary>
+ public static IEnumerable<ExcelFileType> All
+ {
+ get
+ {
+ yield return Excel;
+ yield return ExcelXml;
+ yield return ExcelXmlMacroEnabled;
+ yield return ExcelBinary;
+ }
+ }
+
+ /// <summary>
+ /// Enumerates all file types supported by the ExcelDataReader.
+ /// </summary>
+ public static IEnumerable<ExcelFileType> ReaderSupported
+ {
+ get
+ {
+ yield return Excel;
+ yield return ExcelXml;
+ yield return ExcelXmlMacroEnabled;
+ yield return ExcelBinary;
+ }
+ }
+
+ /// <summary>
+ /// Enumerates all file types supported by the ExcelDataWriter.
+ /// </summary>
+ public static IEnumerable<ExcelFileType> WriterSupported
+ {
+ get
+ {
+ yield return ExcelXml;
+ yield return ExcelXmlMacroEnabled;
+#if NETCOREAPP1_0_OR_GREATER
+ // not supported on .NET framework versions.
+ yield return ExcelBinary;
+#endif
+ }
+ }
+
+
+ /// <summary>
+ /// Gets the ExcelFileType for a given filename.
+ /// </summary>
+ /// <returns>An ExcelFileType or null.</returns>
+ public static ExcelFileType? FindForFilename(string filename)
+ {
+ var ext = Path.GetExtension(filename);
+ return FindForExtension(ext);
+ }
+
+ /// <summary>
+ /// Gets the ExcelFileType for a given file extension.
+ /// </summary>
+ /// <returns>An ExcelFileType or null.</returns>
+ public static ExcelFileType? FindForExtension(string extension)
+ {
+ foreach (var type in All)
+ {
+ if (StringComparer.OrdinalIgnoreCase.Equals(type.Extension, extension))
+ {
+ return type;
+ }
+ }
+ return null;
+ }
+
+ /// <summary>
+ /// Gets the ExcelFileType for a given content type.
+ /// </summary>
+ /// <returns>An ExcelFileType or null.</returns>
+ public static ExcelFileType? FindForContentType(string contentType)
+ {
+ foreach (var type in All)
+ {
+ if (StringComparer.OrdinalIgnoreCase.Equals(type.ContentType, contentType))
+ {
+ return type;
+ }
+ }
+ return null;
+ }
+
+ /// <summary>
+ /// Gets the ExcelFileType for a ExcelWorkbookType.
+ /// </summary>
+ public static ExcelFileType GetForWorkbookType(ExcelWorkbookType type)
+ {
+ switch (type)
+ {
+ case ExcelWorkbookType.Excel:
+ return Excel;
+ case ExcelWorkbookType.ExcelXml:
+ return ExcelXml;
+ case ExcelWorkbookType.ExcelBinary:
+ return ExcelBinary;
+ }
+ throw new NotSupportedException();
+ }
+
+ /// <summary>
+ /// Determines if the string defines a known Excel ContentType.
+ /// </summary>
+ public static bool IsExcelContentType(string contentType)
+ {
+ return FindForContentType(contentType) != null;
+ }
+
+ private ExcelFileType(string extension, string contentType, ExcelWorkbookType workbookType)
+ {
+ this.Extension = extension;
+ this.ContentType = contentType;
+ this.WorkbookType = workbookType;
+ }
+
+ /// <summary>
+ /// Gets the file extension.
+ /// </summary>
+ public string Extension { get; }
+
+ /// <summary>
+ /// Gets the Content-Type.
+ /// </summary>
+ public string ContentType { get; }
+
+ /// <summary>
+ /// Gets the ExcelWorkbookType.
+ /// </summary>
+ public ExcelWorkbookType WorkbookType { get; }
+}