Getting rid of whitespace in a dictionary

Question

I have a dictionary

Dictionary<string, List<string>> dictGenSubs = new Dictionary<string, List<string>>();

How can I make sure that there is no whitespace in any of the records of the dictionary?

Daniel Hilgarth · Accepted Answer · 2013-02-13T12:21:45.927

2

I assume you are talking only about the strings in the list.

To achieve that goal, you can use this code:

dictGenSubs = dictGenSubs.ToDictionary(
                  x => x.Key,
                  x => x.Value
                        .Select(x => x.Replace(" ", string.Empty))
                        .ToList());

This creates a new dictionary with new lists as the values of the dictionary. Each string in each list will be adjusted before being added to the new list.

A more efficient approach would be to update the existing dictionary and the existing lists:

foreach(var list in dictGenSubs.Values)
{
    for(int i = 0; i < list.Count; ++i)
        list[i] = list[i].Replace(" ", string.Empty);
}

edited Feb 13 '13 at 12:21

answered Feb 13 '13 at 12:16

Daniel Hilgarth

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Why are you creating a new dictionary? – svick Feb 13 '13 at 12:17
`Trim()` only removes leading and trailing whitespace, better to use `x.Replace(" ", string.empty)` – Elliot Levin Feb 13 '13 at 12:19
@svick: Because that's the only way this can be written using LINQ. Please see the updated answer for a more efficient implementation. – Daniel Hilgarth Feb 13 '13 at 12:19
@LelloThree: I understood his question like he doesn't want to have leading or trailing whitespace. Re-reading it I agree that this isn't stated anywhere. – Daniel Hilgarth Feb 13 '13 at 12:20
I prefer the non-LINQ method, much more understandable IMO. – ken2k Feb 13 '13 at 12:29
@ken2k: Agreed, me to. But nowadays, everyone wants to do everything with LINQ. So, if there is a more or less reasonable way to do it with LINQ, I provide it. – Daniel Hilgarth Feb 13 '13 at 12:30
Linq has it's place, it'often more understandable than nested loops but it's not the best tool to modify something or use indexes heavily. Then it becomes inefficient and clumsy. – Tim Schmelter Feb 13 '13 at 12:39
@TimSchmelter: I know that, thanks. – Daniel Hilgarth Feb 13 '13 at 12:41

score 0 · Answer 2 · answered Feb 13 '13 at 12:22

0

Do you mean any whitespace at all in any of the strings in each value? Here's a succinctly inefficient way with LINQ:

bool hasWhitespace = dictGenSubs.SelectMany(kv => kv.Value)
       .Any(s => s.Any(char.IsWhiteSpace));

answered Feb 13 '13 at 12:22

devdigital

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I'm fairly sure that he don't want to know if there's a white-space but he wants to get rid of them(see title). – Tim Schmelter Feb 13 '13 at 12:32
Yes, well removing the whitespace before adding them would seem the most logical. Otherwise Daniel's second approach. – devdigital Feb 13 '13 at 12:34

Getting rid of whitespace in a dictionary

2 Answers2