public void TestInvalidEra()
{
DateTimeFormatInfo info = new CultureInfo("en-us").DateTimeFormat;
Assert.Throws<ArgumentOutOfRangeException>(() =>
{
info.GetAbbreviatedEraName(-1);
});
Assert.Throws<ArgumentOutOfRangeException>(() =>
{
info.GetAbbreviatedEraName(2);
});
}