public static IBarcode Encode(string content, UpcENumberSystem numberSystem)
{
if (content == null)
{
throw new ArgumentNullException(nameof(content));
}
if (!Regex.IsMatch(content, @"^[0-9]*$"))
{
throw new InvalidOperationException("Can only encode numerical digits (0-9)");
}
if (numberSystem != UpcENumberSystem.Zero && numberSystem != UpcENumberSystem.One)
{
throw new InvalidOperationException("Only number systems 0 and 1 are supported by UPC E");
}
if (content.Length != 6)
{
throw new InvalidOperationException("Invalid content length. Should be 6");
}
BitList bitlist = EncodeUpcE(content, numberSystem);
return(new Base1DCode(bitlist, BarcodeType.UPCE, content, Constants.Margin));
}
private static string GetUpcAFromUpcE(string content, UpcENumberSystem numberSystem)
{
var firstChar = numberSystem == UpcENumberSystem.Zero ? '0' : '1';
var upcA = firstChar.ToString();
switch (content.Last())
{
case '0':
case '1':
case '2':
upcA += $"{content.Substring(0, 2)}{content.Last()}0000{content.Substring(2, 3)}";
break;
case '3':
upcA += $"{content.Substring(0, 3)}00000{content.Substring(3, 2)}";
break;
case '4':
upcA += $"{content.Substring(0, 4)}00000{content.Substring(4, 1)}";
break;
case '5':
case '6':
case '7':
case '8':
case '9':
upcA += $"{content.Substring(0, 5)}0000{content.Last()}";
break;
}
upcA += CalculatedUpcAChecksum(upcA);
return(upcA);
}
public void Encode(string testCode, UpcENumberSystem numberSystem, string testResult, string kind)
{
IBarcode code = UpcEEncoder.Encode(testCode, numberSystem);
code.Content.Should().Be(testCode);
code.Bounds.X.Should().Be(testResult.Length);
code.Bounds.Y.Should().Be(1);
code.Metadata.CodeKind.Should().Be(kind);
code.Metadata.Dimensions.Should().Be(1);
string encoded = string.Empty;
int i = 0;
foreach (var r in testResult)
{
encoded += code.At(i++, 0) ? "1" : "0";
}
encoded.Should().Be(testResult);
}
private static BitList EncodeUpcE(string content, UpcENumberSystem numberSystem)
{
var result = new BitList();
// Find the correct parity pattern
// To find it we need the check digit of the UPC-A for which this UPC-E barcode encodes
var upcA = GetUpcAFromUpcE(content, numberSystem);
var upcACheckDigit = upcA.Last();
Constants.ParityPatterns parityPatternTable = Constants.ParityPatternTable[upcACheckDigit];
Constants.Parity[] parityPattern = numberSystem == UpcENumberSystem.Zero ?
parityPatternTable.NumberSystemZero : parityPatternTable.NumberSystemOne;
// Start bars
result.AddBit(true, false, true);
// Data bars
for (int i = 0; i < content.Length; i++)
{
char c = content[i];
Constants.EncodedNumber num = Constants.EncodingTable[c];
Constants.Parity parity = parityPattern[i];
if (parity == Constants.Parity.Even)
{
result.AddBit(num.Even);
}
else
{
result.AddBit(num.Odd);
}
}
// Stop bars
result.AddBit(false, true, false, true, false, true);
return(result);
}
