导出Excel是程序很常用到的功能，.Net Core可以借助Open-XML-SDK来导出Excel。
Open-XML-SDK
open-xml-sdk是是微软开源的项目。Open XML SDK是用于Open XML文档(DOCX, XLSX, and PPTX)的开源类库。它可以：
生成Word，Excel，PPT时有非常好的性能
从XML数据源中填充内容到Word文档中
可将单个Word，Excel，PPT分成多个文件或者将多个合并到一个文件中
DOCX => HTML/CSS 和 HTML/CSS => DOCX 提供友好便捷的方式
提取Excel中的数据
用正则表达式查找或者替换DOCX / PPTX中的内容
更新 DOCX / PPTX 中缓存的数据或者嵌入的表格.
文档内容的修改, 例如从文件中删除跟踪的修订或删除不可接受的内容.
依赖 WindowsBase 或 System.IO.Packaging
开源地址：Open-XML-SDK
Nuget：DocumentFormat.OpenXml
示例
首先添加Nuget包引用
直接上代码：
static void Main(string[] args) { var spreadsheetDocument = SpreadsheetDocument.Create("F:\\OpenXml.xlsx", SpreadsheetDocumentType.Workbook); var workbookpart = spreadsheetDocument.AddWorkbookPart(); workbookpart.Workbook = new Workbook(); WorksheetPart worksheetPart = workbookpart.AddNewPart(); worksheetPart.Worksheet = new Worksheet(new SheetData()); Sheets sheets = spreadsheetDocument.WorkbookPart.Workbook.AppendChild(new Sheets()); Sheet sheet = new Sheet() { Id = spreadsheetDocument.WorkbookPart.GetIdOfPart(worksheetPart), SheetId = 1, Name = "Sheet1" }; sheets.Append(sheet); var sheetData = worksheetPart.Worksheet.GetFirstChild(); for (int i = 0; i < 10; i++) { Row row = new Row(); for (int j = 0; j < 10; j++) { Cell dataCell = new Cell(); dataCell.CellValue = new CellValue($"{i + 1}行{j + 1}列"); dataCell.DataType = new EnumValue(CellValues.String); row.AppendChild(dataCell); } sheetData.Append(row); } workbookpart.Workbook.Save(); spreadsheetDocument.Close(); }
导出的Excel如图：
读取Excel
读取Excel的代码会相对简单一些：
static void Main(string[] args) { using (SpreadsheetDocument doc = SpreadsheetDocument.Open(@"F:\OpenXml.xlsx", false)) { WorkbookPart wbPart = doc.WorkbookPart; Sheet mysheet = (Sheet)doc.WorkbookPart.Workbook.Sheets.ChildElements.FirstOrDefault(); Worksheet worksheet = ((WorksheetPart)wbPart.GetPartById(mysheet.Id)).Worksheet; SheetData sheetData = (SheetData)worksheet.ChildElements.FirstOrDefault(); foreach (var row in sheetData.ChildElements) { foreach (var cell in (row as Row).ChildElements) { var cellValue = (cell as Cell).CellValue; if (cellValue != null) { Console.WriteLine(cellValue.Text); } } } } }