What is the fastest way (fastest to execute) to parse the following String into a list of Integers values? I need the values that are specified between the # # marks.
"#1#+#2#+#3#*1.23+#4#/2+#5#" The above String should create a list of Integers:
Use regular expressions...
var input = "#1#+#2#+#3#*1.23+#4#/2+#5#"; var matches = Regex.Matches(input, "#(.*?)#") .Cast<Match>() .Select(m => m.Groups[1].Value) .ToList(); matches.ForEach(Console.WriteLine); Fiddle: http://dotnetfiddle.net/GMqhXZ
Use string.Split to split your values into an array of strings, and then parse them with int.Parse for integers or double.Parse for floating-point values.
If that is your input, you may have to also call Trim on your strings with the characters you want to remove, e.g. '*', '/', '+'.
May be this?
var array = Regex.Matches("#1#+#2#+#3#*1.23+#4#/2+#5#", @"(?<=#)\d+(?=#)") .Cast<Match>() .Select(x => x.Value) .ToArray(); This checks whether # comes before and after a number, if yes matches it.
Here is the ideone demo
The most readable solution would be something like
string text = "#1#+#2#+#3#*1.23+#4#/2+#5#"; foreach (string fragment in text.Split('#')) { int number; if (int.TryParse(fragment, NumberStyles.Integer, CultureInfo.InvariantCulture, out number)) { Console.WriteLine(number); } } Maybe a faster implementation can be found - but if you do not have to parse several million numbers, I would prefer a readable solution.
Splitfunction. But to remove the special characters or just to get the numeric values you can use regex.