c# 读取上传excel转换为DataTable

var files = Request.Files;if (files == null || files.Count == 0)
{return Json(new { code = 1, msg = "未获取到文件" });
}var file = files[0];var dt = ReadExcelToDataTable(file.InputStream);return Json(new { code = 1, msg = "已读取Excel到DataTable" });

        static DataTable ReadExcelToDataTable(Stream stream){DataTable dataTable = new DataTable();// 读取Excel文件XSSFWorkbook workbook = new XSSFWorkbook(stream);ISheet sheet = workbook.GetSheetAt(0); // 获取第一个工作表// 获取列数int columnsCount = sheet.GetRow(0).LastCellNum;// 用于存储列名和对应的重复次数Dictionary<string, int> columnNameCounts = new Dictionary<string, int>();// 创建表头，处理重复的列名for (int i = 0; i < columnsCount; i++){object obj = sheet.GetRow(0).GetCell(i);if (obj == null || obj.ToString() == string.Empty){dataTable.Columns.Add(new DataColumn("Columns" + i.ToString()));}else{//string columnName = sheet.GetRow(0).GetCell(i).StringCellValue;string columnName = obj.ToString();string uniqueColumnName = GetUniqueColumnName(columnName, columnNameCounts);dataTable.Columns.Add(uniqueColumnName);}}// 填充数据for (int i = 1; i <= sheet.LastRowNum; i++){IRow row = sheet.GetRow(i);DataRow dataRow = dataTable.NewRow();for (int j = 0; j < columnsCount; j++){if (row.GetCell(j) != null){dataRow[j] = row.GetCell(j).ToString();}}dataTable.Rows.Add(dataRow);}return dataTable;}static string GetUniqueColumnName(string columnName, Dictionary<string, int> columnNameCounts){if (!columnNameCounts.ContainsKey(columnName)){columnNameCounts[columnName] = 1;return columnName;}else{int count = columnNameCounts[columnName];columnNameCounts[columnName] = count + 1;return $"{columnName}{count + 1}";}}