public static IEnumerable <string> SplitAndKeep(this string @string, char[] delims, StringSplitOptions options = StringSplitOptions.None)
{
var start = 0;
var index = 0;
while ((index = @string.IndexOfAny(delims, start)) != -1)
{
index = Interlocked.Exchange(ref start, index + 1);
if (start - index - 1 > 0 || !options.HasFlag(StringSplitOptions.RemoveEmptyEntries))
{
yield return(@string.Substring(index, start - index - 1));
}
yield return(@string.Substring(start - 1, 1));
}
if (options.HasFlag(StringSplitOptions.RemoveEmptyEntries))
{
if (start < @string.Length)
{
yield return(@string.Substring(start));
}
}
else
{
yield return(@string.Substring(start));
}
}
public static IEnumerable <string[]> GroupedLines(this string str, StringSplitOptions options = SplitOptions)
{
var buffer = new List <string>();
foreach (var line in str.Lines(StringSplitOptions.None))
{
if (string.IsNullOrWhiteSpace(line))
{
if (buffer.Any())
{
yield return(buffer.ToArray());
buffer.Clear();
}
else if (!options.HasFlag(StringSplitOptions.RemoveEmptyEntries))
{
yield return(Array.Empty <string>());
}
}
else
{
buffer.Add(options.HasFlag(StringSplitOptions.TrimEntries) ? line.Trim() : line);
}
}
if (buffer.Any())
{
yield return(buffer.ToArray());
}
}
public static IEnumerable <string> SplitBy(this string value, string delimiter,
StringSplitOptions options = StringSplitOptions.RemoveEmptyEntries)
{
var splitValues = value.Split(new[] { delimiter }, System.StringSplitOptions.None);
if (options.HasFlag(StringSplitOptions.TrimWhiteSpaceFromEntries) ||
options.HasFlag(StringSplitOptions.TrimWhiteSpaceAndRemoveEmptyEntries))
{
splitValues = splitValues.Select(s => s.Trim()).ToArray();
}
if (options.HasFlag(StringSplitOptions.RemoveEmptyEntries) ||
options.HasFlag(StringSplitOptions.TrimWhiteSpaceAndRemoveEmptyEntries))
{
splitValues = splitValues.Where(s => !s.IsNullOrEmpty()).ToArray();
}
return(splitValues);
}
public static IList <string> SplitQuoted(
this string value,
char delimiter,
char quoteChar,
char escapeChar,
StringSplitOptions options)
{
// Remove the escaped and quoted characters, since we don't want to split on those, but leave
// equal length replacements behind so the indexes line up.
string stranged = new Regex($@"\{escapeChar}.").Replace(value, $"{escapeChar}\0");
stranged =
new Regex($@"\{quoteChar}([^\{quoteChar}]|\{escapeChar}.)*\{quoteChar}").Replace(
stranged,
m => new string('\0', m.Length));
Debug.Assert(stranged.Length == value.Length);
var parts = new List <string>();
int oldIndex = -1;
int index = -1;
// use the indext from the mangled string...
while ((index = stranged.IndexOf(delimiter, index + 1)) != -1)
{
// but substring the original (to restore the masked out characters)
string part = value.Substring(oldIndex + 1, index - oldIndex - 1);
if (part.Length > 0 || !options.HasFlag(StringSplitOptions.RemoveEmptyEntries))
{
parts.Add(part);
}
oldIndex = index;
}
{
string part = value.Substring(oldIndex + 1);
if (part.Length > 0 || !options.HasFlag(StringSplitOptions.RemoveEmptyEntries))
{
parts.Add(part);
}
}
return(parts);
}
public static IEnumerable <ReadOnlyMemory <char> > SplitSpan(this string str, char separator, StringSplitOptions options = StringSplitOptions.None)
{
var start = 0;
for (var i = 0; i < str.Length; i++)
{
if (str[i] == separator)
{
var length = i - start;
if (!options.HasFlag(StringSplitOptions.RemoveEmptyEntries) || length > 0)
{
yield return(str.AsMemory(start, i - start));
}
start = i + 1;
}
}
if (start != str.Length)
{
yield return(str.AsMemory(start, str.Length - start));
}
}
public static IEnumerable <string> Split(this string sequence, string separator, StringComparison comparisonType, StringSplitOptions options)
{
var element = default(string);
for (int a = 0, b = sequence.Length, c = separator.Length, d = 0; a < b; a = d)
{
d = sequence.IndexOf(separator, a, comparisonType);
if (d == -1)
{
element = sequence.Substring(a, b - a);
d = b;
}
else
{
element = sequence.Substring(a, d - a);
d += c;
}
if (options.HasFlag(StringSplitOptions.RemoveEmptyEntries) && string.IsNullOrWhiteSpace(element))
{
continue;
}
yield return(element.Trim());
}
}
