Comment lire des fichiers CSV avec des virgules en C#

Why Do .NET Developers Need a Better CSV Solution?

CSV files power data exchange across countless .NET applications. From financial reports to inventory systems, you have the freedom to programmatically create CSV files in just a few lines of code. While libraries like CsvHelper cover basic CSV operations, modern developers face complex scenarios: converting Excel workbooks with formulas, preserving data types during export, and handling enterprise-grade spreadsheet workflows. IronXL addresses these challenges by combining robust CSV writing with comprehensive Excel functionality in a single, handling multiple columns with ease in a single,dependency-free library that follows RFC 4180 standards.

This makes it ideal for developers building a custom .NET CSV writer or .NET CSV parser that supports multiple columns, row-specific functionality affecting only the row being processed, and automatically inferred separators.

Getting Started with IronXL

Installing IronXL takes seconds through NuGet Package Manager:

Install-Package IronXL.Excel

Once installed, add the IronXL namespace to start writing CSV files and working with separated values efficiently:

using IronXL;
class Program
{
    static void Main(string[] args)
    {
        // Create a new workbook and worksheet
        WorkBook workBook = WorkBook.Create();
        WorkSheet workSheet = workBook.CreateWorkSheet("data");
        // Add headers
        workSheet["A1"].Value = "Product";
        workSheet["B1"].Value = "Quantity";
        workSheet["C1"].Value = "Price";
        // Add data
        workSheet["A2"].Value = "Widget";
        workSheet["B2"].Value = 100;
        workSheet["C2"].Value = 19.99;
        // Save as CSV with comma delimiter
        workBook.SaveAsCsv("inventory.csv", ",");
    }
}

using IronXL;
class Program
{
    static void Main(string[] args)
    {
        // Create a new workbook and worksheet
        WorkBook workBook = WorkBook.Create();
        WorkSheet workSheet = workBook.CreateWorkSheet("data");
        // Add headers
        workSheet["A1"].Value = "Product";
        workSheet["B1"].Value = "Quantity";
        workSheet["C1"].Value = "Price";
        // Add data
        workSheet["A2"].Value = "Widget";
        workSheet["B2"].Value = 100;
        workSheet["C2"].Value = 19.99;
        // Save as CSV with comma delimiter
        workBook.SaveAsCsv("inventory.csv", ",");
    }
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

This simple console tester program shows how to write CSV content directly from your C# code, creating a Workbook object that contains our data. The SaveAsCsv method uses a default separator (comma) but allows you to optionally define sep for different locales; this is especially helpful when handling a decimal separator or alternate column separator char. Internally, sep handles array allocation for the output buffer. The mentioned earlier sep parameter allows you to define this character.

We've also demonstrated how to provide a static entry point and show how to do efficient memory management using a statically defined pool of resources, allowing high performance across multiple rows.

Advanced CSV File Creation Techniques

// Load an Excel file with formulas and formatting
WorkBook workBook = WorkBook.Load("financial_report.xlsx");
// IronXL evaluates formulas before export
workBook.EvaluateAll();
// Export to CSV - each worksheet creates a separate CSV file
workBook.SaveAsCsv("report.csv", ",");
// Creates: report.Sheet1.csv, report.Sheet2.csv, etc.

// Load an Excel file with formulas and formatting
WorkBook workBook = WorkBook.Load("financial_report.xlsx");
// IronXL evaluates formulas before export
workBook.EvaluateAll();
// Export to CSV - each worksheet creates a separate CSV file
workBook.SaveAsCsv("report.csv", ",");
// Creates: report.Sheet1.csv, report.Sheet2.csv, etc.

IRON VB CONVERTER ERROR developers@ironsoftware.com

// Assume dataTable contains query results
DataTable dataTable = GetSalesData();
WorkBook workBook = WorkBook.Create();
WorkSheet workSheet = workBook.CreateWorkSheet("sales");
// Import DataTable directly
var row = 1;
foreach (var dataRow in dataTable.Rows)
{
    for (var col = 0; col < dataTable.Columns.Count; col++)
    {
        workSheet.SetCellValue(row, col, dataRow[col].ToString());
    }
    row++;
}
// Export with custom delimiter if needed
workBook.SaveAsCsv("sales_data.csv", ";");

// Assume dataTable contains query results
DataTable dataTable = GetSalesData();
WorkBook workBook = WorkBook.Create();
WorkSheet workSheet = workBook.CreateWorkSheet("sales");
// Import DataTable directly
var row = 1;
foreach (var dataRow in dataTable.Rows)
{
    for (var col = 0; col < dataTable.Columns.Count; col++)
    {
        workSheet.SetCellValue(row, col, dataRow[col].ToString());
    }
    row++;
}
// Export with custom delimiter if needed
workBook.SaveAsCsv("sales_data.csv", ";");

IRON VB CONVERTER ERROR developers@ironsoftware.com

IronXL vs CsvHelper: Side-by-Side Comparison for Writing CSV Files

Consider this employee data export scenario demonstrating CSV parsing and writing workflows.

CsvHelper Implementation:

using (var writer = new StreamWriter("employees.csv"))
using (var csv = new CsvWriter(writer, CultureInfo.InvariantCulture))
{
    csv.WriteRecords(employees);
}

using (var writer = new StreamWriter("employees.csv"))
using (var csv = new CsvWriter(writer, CultureInfo.InvariantCulture))
{
    csv.WriteRecords(employees);
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

IronXL Implementation:

WorkBook workBook = WorkBook.Create();
WorkSheet workSheet = workBook.CreateWorkSheet("employees");
// Add data with automatic type handling
int rowIndex = 1;
foreach (var emp in employees)
{
    workSheet[$"A{rowIndex}"].Value = emp.Name;
    workSheet[$"B{rowIndex}"].Value = emp.Salary;
    workSheet[$"C{rowIndex}"].Value = emp.StartDate;
    rowIndex++;
}
workBook.SaveAsCsv("employees.csv", ",");

WorkBook workBook = WorkBook.Create();
WorkSheet workSheet = workBook.CreateWorkSheet("employees");
// Add data with automatic type handling
int rowIndex = 1;
foreach (var emp in employees)
{
    workSheet[$"A{rowIndex}"].Value = emp.Name;
    workSheet[$"B{rowIndex}"].Value = emp.Salary;
    workSheet[$"C{rowIndex}"].Value = emp.StartDate;
    rowIndex++;
}
workBook.SaveAsCsv("employees.csv", ",");

IRON VB CONVERTER ERROR developers@ironsoftware.com

While CsvHelper efficiently handles straightforward writing columns operations, IronXL provides the flexibility to work with multiple lines, interpolated strings, and dynamic code generation scenarios and even allowing low-level optimizations with constructs like ref struct link.

Developers can enumerate rows matching specific criteria, manage default automatically inferred separators, or even test with simple console programs that expose row-specific functionality and just the key of each entry for debugging.

Enterprise Features and Best Practices

IronXL’s SaveAsCsv method includes enterprise-grade capabilities:

• Custom delimiters: Support for comma, semicolon, tab, or any character (the default separator can be overridden with separator sep)
• Encoding options: UTF-8, UTF-16, and custom encodings
• Formula evaluation: Calculates Excel formulas before export
• Cross-platform support: Works on Windows, Linux, and macOS

Developers can also apply extension methods to access multiple columns for efficient processing or write CSV lines that span multiple lines when text wrapping is required.

Common Issues and Solutions

When working with CSV exports, developers often encounter these challenges:

• Special characters in data: IronXL automatically escapes quotes, commas, and newlines
• Large file handling: Use worksheet ranges to process data in chunks,
• Encoding issues: Specify UTF-8 encoding for international characters
• Missing data types: IronXL preserves numeric and date formats by default

For detailed troubleshooting, visit IronXL's CSV documentation, API reference, and support resources.

Start Building Your CSV Writer Today

IronXL transforms CSV writing from a parsing challenge into a straightforward operation. By combining CSV functionality with Excel workbook support, formula evaluation, and automatic type handling, it eliminates the complexity of managing multiple libraries or manual data conversions.

Ready to streamline your CSV workflows? Start your free trial starting at $liteLicense.