EPPlus应用笔记

C#窗体程序中经常会使用到对数据的输入输出，而Excel文件是比较通用的文本格式，针对功能需求：

• 快速方便读写Excel文件
• 对于未安装Office的机器也能具备生成和读写Excel的能力

通常有NPOI、ClosedXML、EPPlus等类库可供使用，本文对EPPlus的简单使用做一总结。

EPPlus的GitHub网址：https://github.com/EPPlusSoftware/EPPlus
EPPlus版本：5.0.4

读取Excel文件至二维数组：

FileInfo file = new FileInfo(@"数据.xlsx");

ExcelPackage excelPackage = new ExcelPackage(file);
//许可证，必须添加许可证，否则会报错
ExcelPackage.LicenseContext = OfficeOpenXml.LicenseContext.NonCommercial;
//选择读取的数据表
ExcelWorksheet excelWorksheet = excelPackage.Workbook.Worksheets["Sheet1"];
//获取表格数据的最大行数        
int rowNum = excelWorksheet.Dimension.End.Row;
//获取表格数据的最大列数
int columnNum = excelWorksheet.Dimension.End.Column;
//定义存储数据的二维数组
string[,] dataTable = new string[rowNum, columnNum];

//按行读取，存入二维数组dataTable
for (int i = excelWorksheet.Dimension.Start.Row; i <= excelWorksheet.Dimension.End.Row; i++)
{
     
	for (int j = excelWorksheet.Dimension.Start.Column; j <= excelWorksheet.Dimension.End.Column; j++)
    {
     
    	dataTable[i - 1, j - 1] = excelWorksheet.Cells[i, j].Value.ToString();
    }
}

//将数组遍历输出
for (int i = 0; i < dataTable.GetLength(0); i++)
{
     
	for (int j = 0; j < dataTable.GetLength(1); j++)
    {
     
    	Console.Write(dataTable[i, j] + "\t");
    }
    Console.Write("\n");
}
Console.ReadKey();

将数组写入Excel表

//待写入的数组，及Excel表存储位置
string[] str = {
      "1", "5", "10", "15", "20" };
string outputExcelPath = System.Environment.CurrentDirectory + "\\数据.xlsx";
FileInfo file = new FileInfo(outputExcelPath);
//许可证
ExcelPackage.LicenseContext = OfficeOpenXml.LicenseContext.NonCommercial;

//如果文件存在，则读取并写入新的列，若不存在则创建
if (file.Exists)
{
     
	ExcelPackage excelPackage = new ExcelPackage(file);
    //选择读取的数据表
    ExcelWorksheet excelWorksheet = excelPackage.Workbook.Worksheets["Sheet1"];
    //获取表格中已有数据的列数
    int columnNum = excelWorksheet.Dimension.End.Column;
    //写入数据
    excelWorksheet.Cells[1, columnNum + 1].Value = "新数据";
    for (int i = 0; i < str.Length; i++)
    {
     
    	excelWorksheet.Cells[i + 2, columnNum + 1].Value = str[i];
    }
    excelPackage.Save();
}
else
{
     
	file = new FileInfo(outputExcelPath);
    ExcelPackage excelPackage = new ExcelPackage(file);
    //创建新的数据表
    ExcelWorksheet excelWorksheet = excelPackage.Workbook.Worksheets.Add("Sheet1");
    //写入数据
    excelWorksheet.Cells[1, 1].Value = "数据";
    for (int i = 0; i < str.Length; i++)
    {
     
    	excelWorksheet.Cells[i + 2, 1].Value = str[i];
    }
    excelPackage.Save();
}

运行结果：

End