public string ToString(double value, ExpressionFormat info = null)
{
string text;
if (value < MIN_NUMBER || value > MAX_NUMBER)
{
text = ExcelValue.VALUE.ToString();
}
else
{
info ??= ExpressionFormat.General;
var format = info.GetFormat(null);
if (format.NeedsDate)
{
var date = ExcelValue.FromDateSerial(value);
// Should start from beginning in order to use the overriden methods
if (date.HasValue)
{
text = ToString(date.Value, info);
}
else
{
text = ExcelValue.NA.ToString();
}
}
else
{
text = string.Format(culture, format.Format, Convert.ToDecimal(value));
}
}
return(text);
}
public void DateValue_FromDateSerial()
{
Assert.Null(ExcelValue.FromDateSerial(-1));
Assert.Null(ExcelValue.FromDateSerial(0));
Assert.Equal(new DateTime(1900, 1, 1, 6, 0, 0), ExcelValue.FromDateSerial(0.25));
Assert.Equal(new DateTime(1900, 1, 1, 12, 0, 0), ExcelValue.FromDateSerial(0.5));
Assert.Equal(new DateTime(1900, 1, 1, 18, 0, 0), ExcelValue.FromDateSerial(0.75));
Assert.Equal(new DateTime(1900, 1, 1), ExcelValue.FromDateSerial(1));
Assert.Equal(new DateTime(1900, 1, 2), ExcelValue.FromDateSerial(2));
Assert.Equal(new DateTime(1900, 2, 28), ExcelValue.FromDateSerial(59));
Assert.Equal(new DateTime(1900, 3, 1), ExcelValue.FromDateSerial(61));
Assert.Equal(new DateTime(2008, 1, 1), ExcelValue.FromDateSerial(39448));
Assert.Equal(new DateTime(2020, 5, 16), ExcelValue.FromDateSerial(43967));
}