public static String CalculateEntryHash(ACHFile file)
{
var sum =
file
.Batches
.SelectMany(batch => batch.Entries)
.Select(entry => entry.ReceivingDFIIdentification)
.Select(routingNumber => routingNumber.Substring(0, 8))
.Select(substring => Decimal.Parse(substring))
.Sum();
//IF THE SUM OF THE RDFI TRANSIT ROUTING NUMBERS IS A
//NUMBER GREATER THAN TEN DIGITS, REMOVE OR DROP THE
//NUMBER OF DIGITS FROM THE LEFT SIDE OF THE NUMBER
//UNTIL ONLY TEN DIGITS REMAIN. FOR EXAMPLE, IF THE SUM
//OF THE TRANSIT ROUTING NUMBERS IS 234567898765,
//REMOVE THE “23” FOR A HASH OF 4567898765.
var last10 = sum % 10000000000;
return last10.ToString();
}
public static int GetNumberOfLines(ACHFile file)
{
var lines = 1; // file header
foreach (var batch in file.Batches)
{
lines += 2; // batch header + control
lines += batch.Entries.Count;
}
lines += 1; // file control
return lines;
}
internal FileControl(ACHFile file)
{
this.BatchCount = file.Batches.Count;
this.EntryCount = file.Batches.Sum(batch => batch.Entries.Count);
this.TotalCredits = file.Batches.Sum(batch => batch.Control.TotalCredits);
this.TotalDebits = file.Batches.Sum(batch => batch.Control.TotalDebits);
this.BlockCount = (int)Math.Ceiling(ACHFile.GetNumberOfLines(file) / 10m);
this.EntryHash = CalculateEntryHash(file);
}