// Reasonably simple way of computing the maximum/minimum offset
// from either periods or transitions, with or without a tail zone.
private static Offset ComputeOffset <T>(IEnumerable <T> elements,
OffsetExtractor <T> extractor,
DateTimeZone tailZone,
OffsetAggregator aggregator)
{
Preconditions.CheckNotNull(elements, "elements");
Offset ret;
using (var iterator = elements.GetEnumerator())
{
var hasFirst = iterator.MoveNext();
Preconditions.CheckArgument(hasFirst, "iterator", "No transitions / periods specified");
ret = extractor(iterator.Current);
while (iterator.MoveNext())
{
ret = aggregator(ret, extractor(iterator.Current));
}
}
if (tailZone != null)
{
// Effectively a shortcut for picking either tailZone.MinOffset or
// tailZone.MaxOffset
Offset bestFromZone = aggregator(tailZone.MinOffset, tailZone.MaxOffset);
ret = aggregator(ret, bestFromZone);
}
return(ret);
}
public void TestOffsetParse()
{
string text = "P99912:29:12 10/26/17 P5V1_211";
var extractor = OffsetExtractor.Build <Message>(new List <OffsetRule> {
new OffsetRule {
Field = "Code", Offset = 1, Length = 3
},
new OffsetRule {
Field = "TimeStamp", Offset = 4, Length = 17
},
new OffsetRule {
Field = "SenderName", Offset = 22, Length = 8
},
});
var message = extractor.Parse(text);
Assert.AreEqual("999", message.Code);
Assert.AreEqual("12:29:12 10/26/17", message.TimeStamp);
Assert.AreEqual("P5V1_211", message.SenderName);
}
