How to Read CSV Files with Commas in 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
Advanced CSV File Creation Techniques
Converting Excel Workbooks to CSV
IronXL excels at converting existing Excel files to CSV, evaluating formulas, and preserving data integrity. This is essential when writing CSV files that contain both header rows and dynamically generated data.
// 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
When converting multi-sheet workbooks, IronXL automatically generates individual CSV files for each worksheet. Formula calculations execute before export, ensuring accurate data in the final CSV output. But this is not the only feature. The default automatically inferred separator ensures compatibility across regions, and multiple rows or multiple columns are handled seamlessly.
You can also use a nullable sep for dynamic environments where the default supported separators vary.
Output
First, here you can see the CSV files generated from our multi sheet Excel file:
And this is an example comparison of one of the Excel sheets vs. the corresponding CSV file:
Exporting DataTable to CSV
For database-driven applications, IronXL streamlines DataTable exports. We are setting the var to Datarow instead of a typical ref var v to be more clear.
// 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
When importing, each line horizontal set of data from the dataTable.Rows collection becomes a new row in the worksheet. IronXL preserves data types during conversion, that means numbers remain numeric, dates maintain formatting, and text handles special characters correctly without additional configuration.
Output
Here, you can see our mock data source next to the output CSV file:
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
Feature | CsvHelper | IronXL |
---|---|---|
Basic CSV Writing | ✓ | ✓ |
Excel to CSV Conversion | ✗ | ✓ |
Formula Evaluation | ✗ | ✓ |
Multi-sheet Handling | ✗ | ✓ |
Data Type Preservation | Manual | Automatic |
Excel Format Support | ✗ | XLSX, XLS, XLSM |
No MS Office Required | ✓ | ✓ |
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 $749.