Como ler dados do Excel em C#

Imports IronXL
Imports System
Imports System.Linq

' Supported for XLSX, XLS, XLSM, XLTX, CSV and TSV
Dim workBook As WorkBook = WorkBook.Load("sample.xlsx")

' Select worksheet at index 0
Dim workSheet As WorkSheet = workBook.WorkSheets(0)

' Get any existing worksheet
Dim firstSheet As WorkSheet = workBook.DefaultWorkSheet

' Select a cell and return the converted value
Dim cellValue As Integer = workSheet("A2").IntValue

' Read from ranges of cells elegantly.
For Each cell In workSheet("A2:A10")
    Console.WriteLine("Cell {0} has value '{1}'", cell.AddressString, cell.Text)
Next

' Calculate aggregate values such as Min, Max and Sum
Dim sum As Decimal = workSheet("A2:A10").Sum()

' Linq compatible
Dim max As Decimal = workSheet("A2:A10").Max(Function(c) c.DecimalValue)