Cell Values

var workbook = new XLWorkbook();
var ws = workbook.Worksheets.Add("Cell Values");

// Set the titles
ws.Cell(2, 2).Value = "Initial Value";
ws.Cell(2, 3).Value = "Casting";
ws.Cell(2, 4).Value = "Using Get...()";
ws.Cell(2, 5).Value = "Using GetValue<T>()";
ws.Cell(2, 6).Value = "GetString()";
ws.Cell(2, 7).Value = "GetFormattedString()";

//////////////////////////////////////////////////////////////////
// DateTime

// Fill a cell with a date
var cellDateTime = ws.Cell(3, 2);
cellDateTime.Value = new DateTime(2010, 9, 2);
cellDateTime.Style.DateFormat.Format = "yyyy-MMM-dd";

// Extract the date in different ways
DateTime dateTime1 = (DateTime)cellDateTime.Value;
DateTime dateTime2 = cellDateTime.GetDateTime();
DateTime dateTime3 = cellDateTime.GetValue<DateTime>();
String dateTimeString = cellDateTime.GetString();
String dateTimeFormattedString = cellDateTime.GetFormattedString();

// Set the values back to cells
// The apostrophe is to force ClosedXML to treat the date as a string
ws.Cell(3, 3).Value = dateTime1;
ws.Cell(3, 4).Value = dateTime2;
ws.Cell(3, 5).Value = dateTime3;
ws.Cell(3, 6).Value = "'" + dateTimeString;
ws.Cell(3, 7).Value = "'" + dateTimeFormattedString;

//////////////////////////////////////////////////////////////////
// Boolean

// Fill a cell with a boolean
var cellBoolean = ws.Cell(4, 2);
cellBoolean.Value = true;

// Extract the boolean in different ways
Boolean boolean1 = (Boolean)cellBoolean.Value;
Boolean boolean2 = cellBoolean.GetBoolean();
Boolean boolean3 = cellBoolean.GetValue<Boolean>();
String booleanString = cellBoolean.GetString();
String booleanFormattedString = cellBoolean.GetFormattedString();

// Set the values back to cells
// The apostrophe is to force ClosedXML to treat the boolean as a string
ws.Cell(4, 3).Value = boolean1;
ws.Cell(4, 4).Value = boolean2;
ws.Cell(4, 5).Value = boolean3;
ws.Cell(4, 6).Value = "'" + booleanString;
ws.Cell(4, 7).Value = "'" + booleanFormattedString;

//////////////////////////////////////////////////////////////////
// Double

// Fill a cell with a double
var cellDouble = ws.Cell(5, 2);
cellDouble.Value = 1234.567;
cellDouble.Style.NumberFormat.Format = "#,##0.00";

// Extract the double in different ways
Double double1 = (Double)cellDouble.Value;
Double double2 = cellDouble.GetDouble();
Double double3 = cellDouble.GetValue<Double>();
String doubleString = cellDouble.GetString();
String doubleFormattedString = cellDouble.GetFormattedString();

// Set the values back to cells
// The apostrophe is to force ClosedXML to treat the double as a string
ws.Cell(5, 3).Value = double1;
ws.Cell(5, 4).Value = double2;
ws.Cell(5, 5).Value = double3;
ws.Cell(5, 6).Value = "'" + doubleString;
ws.Cell(5, 7).Value = "'" + doubleFormattedString;

//////////////////////////////////////////////////////////////////
// String

// Fill a cell with a string
var cellString = ws.Cell(6, 2);
cellString.Value = "Test Case";

// Extract the string in different ways
String string1 = (String)cellString.Value;
String string2 = cellString.GetString();
String string3 = cellString.GetValue<String>();
String stringString = cellString.GetString();
String stringFormattedString = cellString.GetFormattedString();

// Set the values back to cells
ws.Cell(6, 3).Value = string1;
ws.Cell(6, 4).Value = string2;
ws.Cell(6, 5).Value = string3;
ws.Cell(6, 6).Value = stringString;
ws.Cell(6, 7).Value = stringFormattedString;

//////////////////////////////////////////////////////////////////
// TimeSpan

// Fill a cell with a timeSpan
var cellTimeSpan = ws.Cell(7, 2);
cellTimeSpan.Value = new TimeSpan(1, 2, 31, 45);

// Extract the timeSpan in different ways
TimeSpan timeSpan1 = (TimeSpan)cellTimeSpan.Value;
TimeSpan timeSpan2 = cellTimeSpan.GetTimeSpan();
TimeSpan timeSpan3 = cellTimeSpan.GetValue<TimeSpan>();
String timeSpanString = cellTimeSpan.GetString();
String timeSpanFormattedString = cellTimeSpan.GetFormattedString();

// Set the values back to cells
ws.Cell(7, 3).Value = timeSpan1;
ws.Cell(7, 4).Value = timeSpan2;
ws.Cell(7, 5).Value = timeSpan3;
ws.Cell(7, 6).Value = "'" + timeSpanString;
ws.Cell(7, 7).Value = "'" + timeSpanFormattedString;

//////////////////////////////////////////////////////////////////
// Do some formatting
ws.Columns("B:G").Width = 20;
var rngTitle = ws.Range("B2:G2");
rngTitle.Style.Font.Bold = true;
rngTitle.Style.Fill.BackgroundColor = XLColor.Cyan;

ws.Columns().AdjustToContents();

workbook.SaveAs("CellValues.xlsx");