private static PreParsedInput PreParseInput(string inputStr)
{
var result = new PreParsedInput();
Match matchSingleCharacterDelimeter = INPUT_PARSING_REGEXP_SINGLE_CHAR_DELIMETER.Match(inputStr);
if (matchSingleCharacterDelimeter.Success)
{
result.CustomDelimeters = new string[] { matchSingleCharacterDelimeter.Groups[DELIMETER_GROUP_NAME].Value };
result.NumbersString = matchSingleCharacterDelimeter.Groups[INPUT_NUMBERS_GROUP_NAME].Value;
}
else
{
Match matchManyCharacterDelimeter = INPUT_PARSING_REGEXP_MANY_DELIMETERS.Match(inputStr);
if (matchManyCharacterDelimeter.Success)
{
// string with a list of delimeters in a format "[{delimiter1}][{delimiter2}]..[{delimiterN}]"
string delimetersString = matchManyCharacterDelimeter.Groups[DELIMETER_GROUP_NAME].Value;
// split it to individual delimeters
// option StringSplitOptions.RemoveEmptyEntries is used to remove empty strings
string[] delimeters = delimetersString.Split(new char[] { '[', ']' }, StringSplitOptions.RemoveEmptyEntries);
result.CustomDelimeters = delimeters;
result.NumbersString = matchManyCharacterDelimeter.Groups[INPUT_NUMBERS_GROUP_NAME].Value;
}
else
{
result.NumbersString = inputStr;
}
}
return(result);
}
public IEnumerable <int> ParseNumbers(string inputStr)
{
// if input value is null or empty return empty collection
if (string.IsNullOrWhiteSpace(inputStr))
{
return(new List <int>());
}
PreParsedInput parsedInput = PreParseInput(inputStr);
string[] delimeters = GetAllDelimeters(parsedInput.CustomDelimeters);
return(parsedInput.NumbersString
.Split(delimeters, StringSplitOptions.None)
.Select(x => ConvertToNumber(x)));
}