Read a CSV File in C#

Updated: 2026年6月4日

IronXL 提供了一种通过 LoadCSV 方法在 C# 中读取 CSV 文件的单行解决方案。它支持自定义分隔符和直接转换为 Excel 格式，以便在 .NET 应用程序中进行无缝数据处理。

快速入门：使用IronXL一行加载和转换CSV文件

此示例演示如何通过 IronXL 的 LoadCSV 方法读取 CSV 文件，并以最少的代码将其保存为 Excel 工作簿。

1Install IronXL with NuGet Package Manager
PM > Install-Package IronXL.Excel
```
Install-Package IronXL.Excel
```

2复制并运行这段代码。

WorkBook wb = WorkBook.LoadCSV("data.csv", ExcelFileFormat.XLSX, listDelimiter: ","); wb.SaveAs("output.xlsx");

WorkBook wb = WorkBook.LoadCSV("data.csv", ExcelFileFormat.XLSX, listDelimiter: ","); wb.SaveAs("output.xlsx");

3部署到您的生产环境中进行测试

通过免费试用立即在您的项目中开始使用IronXL

最小工作流程（5 个步骤）

下载并安装 C# CSV 读取库
创建一个 C# 或 VB 项目
将此页面上的代码示例添加到您的项目中
指定 CSV 路径和输出名称及格式
运行项目查看文档

在 .NET 应用程序中读取 CSV 文件

安装用于读取 CSV 文件的 C# 库 (IronXL)
在 C# 中读取 CSV 文件
指定文件格式和分隔符

步骤1

如何安装 IronXL 库？

在 MVC、ASP 或 .NET Core 中使用 IronXL 读取 CSV 文件之前，您需要安装它。下面是一个快速攻略。

为什么要使用 NuGet 包管理器？

在 Visual Studio 中，选择"项目"菜单

管理 NuGet 程序包
搜索 IronXL.Excel
安装

Visual Studio NuGet 软件包管理器安装 IronXL.Excel 库的软件包详情和控制台输出

图 1-IronXL.Excel NuGet 包

哪些是替代安装方法？

或从 Iron Software 网站下载：https://ironsoftware.com/csharp/excel/packages/IronXL.zip

对于使用 Docker 容器的 .NET 开发人员，IronXL.Excel 可以配置在您的 Docker 环境中。该库还支持在 Azure Functions 和 AWS Lambda 上部署，用于基于云的 CSV 处理。

如何使用教程

如何以编程方式读取 CSV 文件？

现在开始项目！

我需要导入哪个命名空间？

添加 IronXL 命名空间：

// This namespace is required to access the IronXL functionalities
using IronXL;

// This namespace is required to access the IronXL functionalities
using IronXL;

Imports IronXL

Imports IronXL

如何加载和转换 CSV 文件？

添加代码，使用 IronXL 和 C# 以编程方式读取 CSV 文件：

// Load the CSV file into a WorkBook object, specifying the file path, format, and delimiter
WorkBook workbook = WorkBook.LoadCSV("Read_CSV_Ex.csv", fileFormat: ExcelFileFormat.XLSX, listDelimiter: ",");

// Access the default worksheet within the loaded workbook
WorkSheet ws = workbook.DefaultWorkSheet;

// Save the workbook as an Excel file with a specified name
workbook.SaveAs("Csv_To_Excel.xlsx");

// Load the CSV file into a WorkBook object, specifying the file path, format, and delimiter
WorkBook workbook = WorkBook.LoadCSV("Read_CSV_Ex.csv", fileFormat: ExcelFileFormat.XLSX, listDelimiter: ",");

// Access the default worksheet within the loaded workbook
WorkSheet ws = workbook.DefaultWorkSheet;

// Save the workbook as an Excel file with a specified name
workbook.SaveAs("Csv_To_Excel.xlsx");

' Load the CSV file into a WorkBook object, specifying the file path, format, and delimiter
Dim workbook As WorkBook = WorkBook.LoadCSV("Read_CSV_Ex.csv", fileFormat:=ExcelFileFormat.XLSX, listDelimiter:=",")

' Access the default worksheet within the loaded workbook
Dim ws As WorkSheet = workbook.DefaultWorkSheet

' Save the workbook as an Excel file with a specified name
workbook.SaveAs("Csv_To_Excel.xlsx")

' Load the CSV file into a WorkBook object, specifying the file path, format, and delimiter
Dim workbook As WorkBook = WorkBook.LoadCSV("Read_CSV_Ex.csv", fileFormat:=ExcelFileFormat.XLSX, listDelimiter:=",")

' Access the default worksheet within the loaded workbook
Dim ws As WorkSheet = workbook.DefaultWorkSheet

' Save the workbook as an Excel file with a specified name
workbook.SaveAs("Csv_To_Excel.xlsx")

有哪些高级 CSV 阅读选项？

IronXL 提供了处理各种配置的 CSV 文件的功能。您可以指定不同的分隔符（分号、制表符、管道）并处理不同编码的文件：

// Example: Reading CSV with custom delimiter
WorkBook workbook = WorkBook.LoadCSV("data.csv",
    fileFormat: ExcelFileFormat.XLSX,
    listDelimiter: ";");  // Using semicolon as delimiter

// Access specific cells after loading
var cellValue = workbook.DefaultWorkSheet["A1"].Value;

// Iterate through rows
foreach (var row in workbook.DefaultWorkSheet.Rows)
{
    // Process each row
    foreach (var cell in row)
    {
        Console.WriteLine(cell.Value);
    }
}

// Example: Reading CSV with custom delimiter
WorkBook workbook = WorkBook.LoadCSV("data.csv",
    fileFormat: ExcelFileFormat.XLSX,
    listDelimiter: ";");  // Using semicolon as delimiter

// Access specific cells after loading
var cellValue = workbook.DefaultWorkSheet["A1"].Value;

// Iterate through rows
foreach (var row in workbook.DefaultWorkSheet.Rows)
{
    // Process each row
    foreach (var cell in row)
    {
        Console.WriteLine(cell.Value);
    }
}

CSV 文件在处理前是什么样子？

记事本中显示动物数据的 CSV 文件，包含月、长颈鹿、大象、犀牛列和 6 个月的种群数据

图 2-记事本中打开的 CSV 文件

LoadCSV 方法如何工作？

创建 Workbook 对象。 LoadCSV 方法指定要读取的 CSV 文件、要读取的格式以及分隔符。在本例中，使用逗号作为分隔符。

创建一个 Worksheet 对象来放置 CSV 内容。然后以新的名称和格式保存文件。当您需要在不同的电子表格格式之间进行转换时，这一过程非常有用。

Excel 电子表格显示 CSV 数据，其中列有月、长颈鹿、大象和犀牛以及 6 个月的动物数量数据

图 3-在 Excel 中打开的 CSV 文件

我能否高效处理大型 CSV 文件？

IronXL 对性能进行了优化，可高效处理大型 CSV 文件。对于处理大量数据集的开发人员，该库在最近的版本中提供了显著的性能改进。在处理大文件时，请考虑以下最佳实践：

// Reading large CSV files with memory optimization
WorkBook workbook = WorkBook.LoadCSV("large_dataset.csv", 
    fileFormat: ExcelFileFormat.XLSX, 
    listDelimiter: ",");

// Process data in chunks
var worksheet = workbook.DefaultWorkSheet;
int rowCount = worksheet.RowCount;
int batchSize = 1000;

for (int i = 0; i < rowCount; i += batchSize)
{
    // Process rows in batches
    var endIndex = Math.Min(i + batchSize, rowCount);
    for (int j = i; j < endIndex; j++)
    {
        var row = worksheet.GetRow(j);
        // Process individual row
    }
}

// Reading large CSV files with memory optimization
WorkBook workbook = WorkBook.LoadCSV("large_dataset.csv", 
    fileFormat: ExcelFileFormat.XLSX, 
    listDelimiter: ",");

// Process data in chunks
var worksheet = workbook.DefaultWorkSheet;
int rowCount = worksheet.RowCount;
int batchSize = 1000;

for (int i = 0; i < rowCount; i += batchSize)
{
    // Process rows in batches
    var endIndex = Math.Min(i + batchSize, rowCount);
    for (int j = i; j < endIndex; j++)
    {
        var row = worksheet.GetRow(j);
        // Process individual row
    }
}

Imports System
Imports IronXL

' Reading large CSV files with memory optimization
Dim workbook As WorkBook = WorkBook.LoadCSV("large_dataset.csv", 
                                            fileFormat:=ExcelFileFormat.XLSX, 
                                            listDelimiter:=",")

' Process data in chunks
Dim worksheet = workbook.DefaultWorkSheet
Dim rowCount As Integer = worksheet.RowCount
Dim batchSize As Integer = 1000

For i As Integer = 0 To rowCount - 1 Step batchSize
    ' Process rows in batches
    Dim endIndex As Integer = Math.Min(i + batchSize, rowCount)
    For j As Integer = i To endIndex - 1
        Dim row = worksheet.GetRow(j)
        ' Process individual row
    Next
Next

Imports System
Imports IronXL

' Reading large CSV files with memory optimization
Dim workbook As WorkBook = WorkBook.LoadCSV("large_dataset.csv", 
                                            fileFormat:=ExcelFileFormat.XLSX, 
                                            listDelimiter:=",")

' Process data in chunks
Dim worksheet = workbook.DefaultWorkSheet
Dim rowCount As Integer = worksheet.RowCount
Dim batchSize As Integer = 1000

For i As Integer = 0 To rowCount - 1 Step batchSize
    ' Process rows in batches
    Dim endIndex As Integer = Math.Min(i + batchSize, rowCount)
    For j As Integer = i To endIndex - 1
        Dim row = worksheet.GetRow(j)
        ' Process individual row
    Next
Next

如何将 CSV 数据导出为其他格式？

阅读 CSV 文件后，您可能需要将数据导出为各种格式。 IronXL 支持多种导出选项，包括 XLSX 到 CSV 的转换、JSON、XML 和 HTML。以下是导出为不同格式的方法：

// Load CSV and export to multiple formats
WorkBook workbook = WorkBook.LoadCSV("input.csv", ExcelFileFormat.XLSX, ",");

// Export to different formats
workbook.SaveAs("output.xlsx"); // Excel format
workbook.SaveAsJson("output.json"); // JSON format
workbook.SaveAsXml("output.xml"); // XML format

// Export specific worksheet to CSV with custom delimiter
workbook.DefaultWorkSheet.SaveAsCsv("output_custom.csv", ";");

// Load CSV and export to multiple formats
WorkBook workbook = WorkBook.LoadCSV("input.csv", ExcelFileFormat.XLSX, ",");

// Export to different formats
workbook.SaveAs("output.xlsx"); // Excel format
workbook.SaveAsJson("output.json"); // JSON format
workbook.SaveAsXml("output.xml"); // XML format

// Export specific worksheet to CSV with custom delimiter
workbook.DefaultWorkSheet.SaveAsCsv("output_custom.csv", ";");

如何在 Web 应用程序中处理 CSV 数据？

对于 ASP.NET 开发人员，IronXL.Excel 可为在 Web 应用程序中读取 CSV 文件提供无缝集成。您可以在 MVC 或 Web API 项目中上传和处理 CSV 文件：

// Example: Processing uploaded CSV file in ASP.NET
public ActionResult UploadCSV(HttpPostedFileBase file)
{
    if (file != null && file.ContentLength > 0)
    {
        // Save uploaded file temporarily
        var fileName = Path.GetFileName(file.FileName);
        var path = Path.Combine(Server.MapPath("~/App_Data/"), fileName);
        file.SaveAs(path);
        
        // Load and process CSV
        WorkBook workbook = WorkBook.LoadCSV(path, ExcelFileFormat.XLSX, ",");
        
        // Convert to DataTable for easy display
        var dataTable = workbook.DefaultWorkSheet.ToDataTable();
        
        // Clean up temporary file
        System.IO.File.Delete(path);
        
        return View(dataTable);
    }
    return RedirectToAction("Index");
}

// Example: Processing uploaded CSV file in ASP.NET
public ActionResult UploadCSV(HttpPostedFileBase file)
{
    if (file != null && file.ContentLength > 0)
    {
        // Save uploaded file temporarily
        var fileName = Path.GetFileName(file.FileName);
        var path = Path.Combine(Server.MapPath("~/App_Data/"), fileName);
        file.SaveAs(path);
        
        // Load and process CSV
        WorkBook workbook = WorkBook.LoadCSV(path, ExcelFileFormat.XLSX, ",");
        
        // Convert to DataTable for easy display
        var dataTable = workbook.DefaultWorkSheet.ToDataTable();
        
        // Clean up temporary file
        System.IO.File.Delete(path);
        
        return View(dataTable);
    }
    return RedirectToAction("Index");
}

' Example: Processing uploaded CSV file in ASP.NET
Public Function UploadCSV(file As HttpPostedFileBase) As ActionResult
    If file IsNot Nothing AndAlso file.ContentLength > 0 Then
        ' Save uploaded file temporarily
        Dim fileName = Path.GetFileName(file.FileName)
        Dim path = Path.Combine(Server.MapPath("~/App_Data/"), fileName)
        file.SaveAs(path)
        
        ' Load and process CSV
        Dim workbook As WorkBook = WorkBook.LoadCSV(path, ExcelFileFormat.XLSX, ",")
        
        ' Convert to DataTable for easy display
        Dim dataTable = workbook.DefaultWorkSheet.ToDataTable()
        
        ' Clean up temporary file
        System.IO.File.Delete(path)
        
        Return View(dataTable)
    End If
    Return RedirectToAction("Index")
End Function

' Example: Processing uploaded CSV file in ASP.NET
Public Function UploadCSV(file As HttpPostedFileBase) As ActionResult
    If file IsNot Nothing AndAlso file.ContentLength > 0 Then
        ' Save uploaded file temporarily
        Dim fileName = Path.GetFileName(file.FileName)
        Dim path = Path.Combine(Server.MapPath("~/App_Data/"), fileName)
        file.SaveAs(path)
        
        ' Load and process CSV
        Dim workbook As WorkBook = WorkBook.LoadCSV(path, ExcelFileFormat.XLSX, ",")
        
        ' Convert to DataTable for easy display
        Dim dataTable = workbook.DefaultWorkSheet.ToDataTable()
        
        ' Clean up temporary file
        System.IO.File.Delete(path)
        
        Return View(dataTable)
    End If
    Return RedirectToAction("Index")
End Function

如何处理包含复杂数据的 CSV 文件？

在处理包含公式、特殊字符或混合数据类型的 CSV 文件时，IronXL 提供了强大的处理能力。您可以使用公式和适当格式化单元格数据：

// Handle CSV with special requirements
WorkBook workbook = WorkBook.LoadCSV("complex_data.csv", 
    ExcelFileFormat.XLSX, 
    listDelimiter: ",");

var worksheet = workbook.DefaultWorkSheet;

// Apply formatting to cells
worksheet["A1:A10"].Style.Font.Bold = true;
worksheet["B1:B10"].FormatString = "$#,##0.00"; // Currency format

// Add formulas after loading CSV data
worksheet["D1"].Formula = "=SUM(B1:B10)";

// Handle CSV with special requirements
WorkBook workbook = WorkBook.LoadCSV("complex_data.csv", 
    ExcelFileFormat.XLSX, 
    listDelimiter: ",");

var worksheet = workbook.DefaultWorkSheet;

// Apply formatting to cells
worksheet["A1:A10"].Style.Font.Bold = true;
worksheet["B1:B10"].FormatString = "$#,##0.00"; // Currency format

// Add formulas after loading CSV data
worksheet["D1"].Formula = "=SUM(B1:B10)";

Imports IronXL

' Handle CSV with special requirements
Dim workbook As WorkBook = WorkBook.LoadCSV("complex_data.csv", ExcelFileFormat.XLSX, listDelimiter:=",")

Dim worksheet = workbook.DefaultWorkSheet

' Apply formatting to cells
worksheet("A1:A10").Style.Font.Bold = True
worksheet("B1:B10").FormatString = "$#,##0.00" ' Currency format

' Add formulas after loading CSV data
worksheet("D1").Formula = "=SUM(B1:B10)"

Imports IronXL

' Handle CSV with special requirements
Dim workbook As WorkBook = WorkBook.LoadCSV("complex_data.csv", ExcelFileFormat.XLSX, listDelimiter:=",")

Dim worksheet = workbook.DefaultWorkSheet

' Apply formatting to cells
worksheet("A1:A10").Style.Font.Bold = True
worksheet("B1:B10").FormatString = "$#,##0.00" ' Currency format

' Add formulas after loading CSV data
worksheet("D1").Formula = "=SUM(B1:B10)"

库快速访问

IronXL API 参考文档

使用便捷的 IronXL API 参考文档，了解更多并分享如何在 Excel 电子表格中合并、取消合并和处理单元格。

IronXL API 参考文档

常见问题解答

如何用 C# 快速读取 CSV 文件？

IronXL 提供了使用 LoadCSV 方法在 C# 中读取 CSV 文件的单行解决方案。只需使用WorkBook wb = WorkBook.LoadCSV（"data.csv"，ExcelFileFormat.XLSX，listDelimiter: ","）；这将加载 CSV 文件，并允许您使用 wb.SaveAs("output.xlsx") 将其保存为 Excel 工作簿。