How to check if list contains all string of another list

Question

I have a object list. That object contains a string List. Like that:

public class ObjectA
{
    ...
    IList<string> StringList;
}

And I have a list of words to search on StringList. I need to search on a ObjectA list, and find all ObjectA that have all words (parts of all words).

So I did that:

 List<ObjectA> myObjectList;
 List<string> wordsToFind;  

 var result = myObjectList.Where(objectA => wordsToFind.All(objectA.StringList.Contains));

The problem is my result is getting only whole words (equals). I would like to get results that contains parts of my wordsToFind.

Example

wordsToFind = {"tes","don"};
StringListElement = {"test", "done"}

Should return on my select.

How can I do that?

list a contain all word in list b? how about order? is it 100% match or? — Maytham Fahmi, Feb 27 '19 at 11:58
It would be awesome if you could provide a [mcve]. Be sure to provide sample inputs **and expected results based on those sample inputs**. — mjwills, Feb 27 '19 at 12:00
Do you want ordinal comparison? https://stackoverflow.com/a/498722/34092 — mjwills, Feb 27 '19 at 12:02

TheGeneral · Accepted Answer · 2019-02-27T12:20:55.653

5

IndexOf is probably where you want to be, or one of its overloads

Reports the zero-based index of the first occurrence of a specified Unicode character or string within this instance. The method returns -1 if the character or string is not found in this instance.

List<ObjectA> myObjectList;
List<string> wordsToFind;  

var result = myObjectList.Where(x => x.StringList.All(y => wordsToFind.Any(z => y.IndexOf(z) >= 0)));

Also note the time complexity of this is atrocious

Update

Full Demo Here

Also note, if you want case insensitivity use

y.IndexOf(z, StringComparison.InvariantCultureIgnoreCase)

or one of the following

CurrentCulture Compare strings using culture-sensitive sort rules and the current culture.
CurrentCultureIgnoreCase Compare strings using culture-sensitive sort rules, the current culture, and ignoring the case of the strings being compared.
InvariantCultureCompare strings using culture-sensitive sort rules and the invariant culture.
InvariantCultureIgnoreCase Compare strings using culture-sensitive sort rules, the invariant culture, and ignoring the case of the strings being compared.
Ordinal Compare strings using ordinal (binary) sort rules.
OrdinalIgnoreCase Compare strings using ordinal (binary) sort rules and ignoring the case of the strings being compared.

edited Feb 27 '19 at 12:20

answered Feb 27 '19 at 12:00

TheGeneral

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Thanks, Perfomance will not be a problem I guess, the lists are small. I liked your suggestion, but it is always returning empty result, idk why – Paul Feb 27 '19 at 12:15
2

@Paul added online demo – TheGeneral Feb 27 '19 at 12:21
Thanks for details... I explained my needs wrong I think. All words from my search must be in my list, but I can have words on my StringList that are not on my search. I modified your sample, that should return both objects: https://dotnetfiddle.net/QqshRh – Paul Feb 27 '19 at 12:57
1

I modified your code and its working fine now! https://dotnetfiddle.net/z7Q3eW Thanks – Paul Feb 27 '19 at 13:46
@Paul thanks I was asleep heh, I'll fix the answer for future readers – TheGeneral Feb 27 '19 at 22:07

score 1 · Answer 2 · answered Feb 27 '19 at 12:22

The ways to do this is by using a combination of Any and All.

You need to check if all the elements of wordsToFind are substring of any elements in StringList

bool result = wordsToFind.All(word => currentObject.StringList.Any(str => str.Contains(word));

This is for one object out of the list of Objects. You can again apply All to that list.

GoldenAge · Answer 3 · 2019-02-27T13:09:42.383

I think this should work for you

var wordsToFind = new List<string>{ "tes","don"};
var data= new List<ObjectA>()
{
    new ObjectA()
    {
        StringList = new List<string>{"test", "done", "blah"}
    },
    new ObjectA()
    {
        StringList = new List<string>{"test2", "done2", "blah2"}
    }
};

var result = (from item in data.Select(x => x.StringList)
              from bar in item
              from word in wordsToFind
              where bar.Contains(word)
              select bar)
              .ToList();

The result should give you

"test", "done","test2", "done2"

How to check if list contains all string of another list

3 Answers3