DataValidationType Enum

workbook.LoadDocument("Documents\\DataValidation.xlsx");
Worksheet worksheet = workbook.Worksheets[0];

// Restrict data entry to a number within limits.
DataValidation validation = worksheet.DataValidations.Add(worksheet["F4:F11"], DataValidationType.Decimal, DataValidationOperator.Between, 10, 40);

// Change the validation operator and criteria.
// Range F4:F11 should contain numbers greater than or equal 20.
validation.Operator = DataValidationOperator.GreaterThanOrEqual;
validation.Criteria = 20;
validation.Criteria2 = ValueObject.Empty;

// Highlight data validation ranges.
int[] MyColorScheme = new int[] { 0xFFC4C4, 0xFFD9D9, 0xFFF6F6, 0xFFECEC, 0xE9D3D3 };
for (int i = 0; i < worksheet.DataValidations.Count; i++)
{
    worksheet.DataValidations[i].Range.FillColor = Color.FromArgb(MyColorScheme[i]);
}

workbook.LoadDocument("Documents\DataValidation.xlsx")
Dim worksheet As Worksheet = workbook.Worksheets(0)

' Restrict data entry to a number within limits.
Dim validation As DataValidation = worksheet.DataValidations.Add(worksheet("F4:F11"), DataValidationType.Decimal, DataValidationOperator.Between, 10, 40)

' Change the validation operator and criteria.
' Range F4:F11 should contain numbers greater than or equal 20.
validation.Operator = DataValidationOperator.GreaterThanOrEqual
validation.Criteria = 20
validation.Criteria2 = ValueObject.Empty

' Highlight data validation ranges.
Dim MyColorScheme() As Integer = { &HFFC4C4, &HFFD9D9, &HFFF6F6, &HFFECEC, &HE9D3D3 }
For i As Integer = 0 To worksheet.DataValidations.Count - 1
    worksheet.DataValidations(i).Range.FillColor = Color.FromArgb(MyColorScheme(i))
Next i