public class DataValidation 

DataValidation validation0= new DataValidation( ValidationType.WholeNumber, new DataValidationRangeCondition( RangeConditionType.Between, -100, 100 ) );

DataValidation validation1 = DataValidation.Create( ValidationType.TextLength, new DataValidationRangeCondition( RangeConditionType.Between, 5, 10 ) );

DataValidation validation2= DataValidation.Create( ValidationType.WholeNumber, new DataValidationSingleCondition( SingleConditionType.Equal, 6 ) );

//Changes the validation condition
validation0.Condition = new DataValidationSingleCondition( SingleConditionType.GreaterThan, 7 ) );

using( var workbook = Workbook.Create( "AddDataValidation.xlsx" ) ) { 

// Gets the first Worksheet; a Workbook always contains at least 1 Worksheet. 
var worksheet = workbook.Worksheets[ 0 ]; 

// Creates a new DataValidation and assigns it to Cells A1 to A3. 
var dataValidation = new DataValidation( ValidationType.Decimal, DataComparisonType.LessThanOrEqual ) { Value = 10 }; dataValidation.SetError( "My Error", "Value must under 10", DataValidationErrorStyle.Warning ); worksheet.Cells[ "A1", "A3" ].DataValidation = dataValidation; 

// Saves Workbook to disk; 
workbook.Save(); }