IronXLで.NET Core CSV リーダーを使用する方法: 実例

public record Customer(string Name, int Age, string City)
{
    public bool IsValid() => !string.IsNullOrEmpty(Name) && Age > 0;
}

// Parse CSV rows into typed objects
var customers = new List<Customer>();
for (int row = 2; row <= worksheet.RowCount; row++)
{
    var customer = new Customer(
        Name: worksheet[$"A{row}"].StringValue,
        Age:  worksheet[$"B{row}"].IntValue,
        City: worksheet[$"C{row}"].StringValue
    );
    if (customer.IsValid())
        customers.Add(customer);
}
// Output the records
foreach (var record in customers)
{
    Console.WriteLine($"Customer: {record.Name}, Age: {record.Age}, City: {record.City}");
}

Imports System
Imports System.Collections.Generic

Public Class Customer
    Public Property Name As String
    Public Property Age As Integer
    Public Property City As String

    Public Sub New(name As String, age As Integer, city As String)
        Me.Name = name
        Me.Age = age
        Me.City = city
    End Sub

    Public Function IsValid() As Boolean
        Return Not String.IsNullOrEmpty(Name) AndAlso Age > 0
    End Function
End Class

' Parse CSV rows into typed objects
Dim customers As New List(Of Customer)()
For row As Integer = 2 To worksheet.RowCount
    Dim customer As New Customer(
        Name:=worksheet($"A{row}").StringValue,
        Age:=worksheet($"B{row}").IntValue,
        City:=worksheet($"C{row}").StringValue
    )
    If customer.IsValid() Then
        customers.Add(customer)
    End If
Next

' Output the records
For Each record In customers
    Console.WriteLine($"Customer: {record.Name}, Age: {record.Age}, City: {record.City}")
Next

// Load a DataTable from your data source
DataTable exportTable = GetProcessedData(); // your data source method

// Create a new workbook and populate it from the DataTable
WorkBook outputWorkbook = WorkBook.Create(ExcelFileFormat.XLSX);
WorkSheet outputSheet = outputWorkbook.DefaultWorkSheet;

// Write headers from DataTable columns
for (int col = 0; col < exportTable.Columns.Count; col++)
{
    outputSheet[0, col].Value = exportTable.Columns[col].ColumnName;
}

// Write rows
for (int row = 0; row < exportTable.Rows.Count; row++)
{
    for (int col = 0; col < exportTable.Columns.Count; col++)
    {
        outputSheet[row + 1, col].Value = exportTable.Rows[row][col]?.ToString();
    }
}

// Save as CSV
outputWorkbook.SaveAsCsv("output.csv", delimiter: ",");
Console.WriteLine("Export complete.");

Imports System.Data

' Load a DataTable from your data source
Dim exportTable As DataTable = GetProcessedData() ' your data source method

' Create a new workbook and populate it from the DataTable
Dim outputWorkbook As WorkBook = WorkBook.Create(ExcelFileFormat.XLSX)
Dim outputSheet As WorkSheet = outputWorkbook.DefaultWorkSheet

' Write headers from DataTable columns
For col As Integer = 0 To exportTable.Columns.Count - 1
    outputSheet(0, col).Value = exportTable.Columns(col).ColumnName
Next

' Write rows
For row As Integer = 0 To exportTable.Rows.Count - 1
    For col As Integer = 0 To exportTable.Columns.Count - 1
        outputSheet(row + 1, col).Value = exportTable.Rows(row)(col)?.ToString()
    Next
Next

' Save as CSV
outputWorkbook.SaveAsCsv("output.csv", delimiter:=","c)
Console.WriteLine("Export complete.")

WorkBook workbook = WorkBook.LoadCSV("large-dataset.csv",
    fileFormat: ExcelFileFormat.XLSX,
    listDelimiter: ",");
WorkSheet worksheet = workbook.DefaultWorkSheet;

int batchSize = 1000;
int totalRows = worksheet.RowCount;

for (int start = 1; start <= totalRows; start += batchSize)
{
    int end = Math.Min(start + batchSize - 1, totalRows);
    for (int row = start; row <= end; row++)
    {
        string id   = worksheet[$"A{row}"].StringValue;
        string name = worksheet[$"B{row}"].StringValue;
        // Process each record here
        Console.WriteLine($"Row {row}: {id} - {name}");
    }
    Console.WriteLine($"Processed batch {start}-{end}");
}

Imports System

Dim workbook As WorkBook = WorkBook.LoadCSV("large-dataset.csv", fileFormat:=ExcelFileFormat.XLSX, listDelimiter:=",")
Dim worksheet As WorkSheet = workbook.DefaultWorkSheet

Dim batchSize As Integer = 1000
Dim totalRows As Integer = worksheet.RowCount

For start As Integer = 1 To totalRows Step batchSize
    Dim [end] As Integer = Math.Min(start + batchSize - 1, totalRows)
    For row As Integer = start To [end]
        Dim id As String = worksheet($"A{row}").StringValue
        Dim name As String = worksheet($"B{row}").StringValue
        ' Process each record here
        Console.WriteLine($"Row {row}: {id} - {name}")
    Next
    Console.WriteLine($"Processed batch {start}-{end}")
Next

// Apply license key at application startup
IronXl.License.LicenseKey = "YOUR-LICENSE-KEY-HERE";

// Then proceed with CSV reading as normal
WorkBook workbook = WorkBook.LoadCSV("data.csv",
    fileFormat: ExcelFileFormat.XLSX,
    listDelimiter: ",");
WorkSheet worksheet = workbook.DefaultWorkSheet;
Console.WriteLine($"Loaded {worksheet.RowCount} rows from CSV.");

Imports IronXl

' Apply license key at application startup
License.LicenseKey = "YOUR-LICENSE-KEY-HERE"

' Then proceed with CSV reading as normal
Dim workbook As WorkBook = WorkBook.LoadCSV("data.csv", fileFormat:=ExcelFileFormat.XLSX, listDelimiter:=",")
Dim worksheet As WorkSheet = workbook.DefaultWorkSheet
Console.WriteLine($"Loaded {worksheet.RowCount} rows from CSV.")