ExcelDataReader`がExcelファイルを書き込めない理由とIronXLによる解決方法

using IronXL;
// Your first IronXL application
class Program
{
    static void Main()
    {
        // Create workbook
        WorkBook workBook = WorkBook.Create();
        WorkSheet sheet = workBook.CreateWorkSheet("Data");    
        // Write your data
        sheet["A1"].Value = "Hello Excel";
        // Save to file
        workBook.SaveAs("output.xlsx");
    }
}

Imports IronXL

' Your first IronXL application
Class Program
    Shared Sub Main()
        ' Create workbook
        Dim workBook As WorkBook = WorkBook.Create()
        Dim sheet As WorkSheet = workBook.CreateWorkSheet("Data")
        ' Write your data
        sheet("A1").Value = "Hello Excel"
        ' Save to file
        workBook.SaveAs("output.xlsx")
    End Sub
End Class

using IronXL;
// Create a new Excel file
WorkBook workBook = WorkBook.Create();
WorkSheet sheet = workBook.CreateWorkSheet("Report");
// Write values to specific cells
sheet["A1"].Value = "Product";
sheet["B1"].Value = "Quantity";
sheet["A2"].Value = "Widget";
sheet["B2"].Value = 100;
// Save the file
workBook.SaveAs("inventory.xlsx");

Imports IronXL

' Create a new Excel file
Dim workBook As WorkBook = WorkBook.Create()
Dim sheet As WorkSheet = workBook.CreateWorkSheet("Report")

' Write values to specific cells
sheet("A1").Value = "Product"
sheet("B1").Value = "Quantity"
sheet("A2").Value = "Widget"
sheet("B2").Value = 100

' Save the file
workBook.SaveAs("inventory.xlsx")

// Write formulas
sheet["C1"].Value = "Total";
sheet["C2"].Formula = "=B2*1.5";
// Write ranges efficiently
sheet["A3:A10"].Value = "Item";
// Apply formatting while writing
sheet["B2"].Style.Font.Bold = true;
sheet["B2"].Style.BackgroundColor = "#FFFF00";
// Add borders and alignment
sheet["A1:C1"].Style.Border.TopBorder = IronXL.Styles.BorderType.Thick;
sheet["A1:C1"].Style.HorizontalAlignment = IronXL.Styles.HorizontalAlignment.Center;

' Write formulas
sheet("C1").Value = "Total"
sheet("C2").Formula = "=B2*1.5"
' Write ranges efficiently
sheet("A3:A10").Value = "Item"
' Apply formatting while writing
sheet("B2").Style.Font.Bold = True
sheet("B2").Style.BackgroundColor = "#FFFF00"
' Add borders and alignment
sheet("A1:C1").Style.Border.TopBorder = IronXL.Styles.BorderType.Thick
sheet("A1:C1").Style.HorizontalAlignment = IronXL.Styles.HorizontalAlignment.Center

// Read with ExcelDataReader
List<string> data = new List<string>();
using (var stream = File.Open("source.xlsx", FileMode.Open))
{
    using (var reader = ExcelReaderFactory.CreateReader(stream))
    {
        while (reader.Read())
        {
            data.Add(reader.GetString(0));
        }
    }
}
// Cannot write back to Excel - need another library!

Imports System.IO
Imports ExcelDataReader

Dim data As New List(Of String)()
Using stream = File.Open("source.xlsx", FileMode.Open)
    Using reader = ExcelReaderFactory.CreateReader(stream)
        While reader.Read()
            data.Add(reader.GetString(0))
        End While
    End Using
End Using
' Cannot write back to Excel - need another library!

// Read and write with IronXL
WorkBook workBook = WorkBook.Load("source.xlsx");
WorkSheet sheet = workBook.DefaultWorkSheet;
// Read existing data
string originalValue = sheet["A1"].StringValue;
// Modify and add new data
sheet["A1"].Value = originalValue.ToUpper();
sheet["B1"].Value = DateTime.Now;
// Add rows and columns dynamically
sheet.InsertRow(2); // Insert a new row at position 2
sheet.InsertColumn(3); // Insert a new column at position C
// Save as new file
workBook.SaveAs("modified.xlsx");

' Read and write with IronXL
Dim workBook As WorkBook = WorkBook.Load("source.xlsx")
Dim sheet As WorkSheet = workBook.DefaultWorkSheet
' Read existing data
Dim originalValue As String = sheet("A1").StringValue
' Modify and add new data
sheet("A1").Value = originalValue.ToUpper()
sheet("B1").Value = DateTime.Now
' Add rows and columns dynamically
sheet.InsertRow(2) ' Insert a new row at position 2
sheet.InsertColumn(3) ' Insert a new column at position C
' Save as new file
workBook.SaveAs("modified.xlsx")