C# String Search with multiple substrings

So I'm working on a filter for a resource list and one of the filters is the Name property(string).

As a(dumb) example : resource name is "Big,Red/Square Table" and the filter is "Table Red", it should be a valid resource

This is what I could come up with using the little time I had:

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter) || filter == "") return;

    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var validResources = new List<ResourceModel>();



    foreach (var resource in model.ResourcesViewModel.Resources)

    {

        var filterSubstrings =

            filter

            .ToLower()

            .Split(separators)

            .ToList();



        var resourceSubstrings =

            resource.Name

            .ToLower()

            .Split(separators)

            .ToList();



        resourceSubstrings.ForEach(substring => {

            if (filterSubstrings.Contains(substring))

                filterSubstrings.RemoveAll(sub => sub == substring);

        });



        if (filterSubstrings.Count == 0)

            validResources.Add(resource);

    }



    model.ResourcesViewModel.Resources = validResources;

}

Should I take a different approach for this?

EDIT:
Ended up going with this until I figure out RegEx

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter)) return;



    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var filterSubstrings =

        filter

            .ToLower()

            .Split(separators)

            .ToList();



    var validResources = model.ResourcesViewModel.Resources

        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

        .ToList();



    model.ResourcesViewModel.Resources = validResources;

}

edited Nov 20 '18 at 9:12

asked Nov 16 '18 at 18:41

Xeyth

606

3

Yeah. Definitely look towards a regex solution - you'll definitely have more concise code. There are other ways to skin this cat, but you'd have to be digging back to your comp sci 101 past and thinking about dynamic programming (at least that's what's coming to my mind, LOL). Single responsibility principle based approach also might make your life a lesser hell, here, as well. In both the regex and non-regex approaches, try to leverage an immutability based approach. You're going to really appreciate that you didn't change things in-place, later on.

– code4life
Nov 16 '18 at 18:49

I haven't used too much RegEx though, I know it's damn powerful. Is there a way to generate proper regex patterns based on ones input?

– Xeyth
Nov 16 '18 at 18:56

1

@Xeyth, To add on code4life excellent comment. I will also clarify, about specific point, if the method you are working with, only need the resource list, you do not want to let the method "know" all of your object and his hierarchy. some of the reasons for that is: in case the hierarchy will change, or you will want to use this logic in some other part of your application. you don't need to pass things that the method doesn't care, nor should you.

– Orel Eraki
Nov 16 '18 at 18:57

@Xeyth: absolutely. If you're using .NET 4.5 or higher, it gets even easier since you get to leverage string interpolation. For instance, $"{your variable here}regex expression here" - that's just a very raw, off-the-cuff example. I strongly suggest googling regex, you are not going to need a very complex regex, for what you are trying to do.

– code4life
Nov 16 '18 at 18:59

1

@Xeyth, If you only wants to "beautify" your method, you can work with .Intersect or .All, which is immutable and also, almost gives you the solution. e.g: filterSubstrings.Intersect(resourceSubstrings).Count() == filterSubstrings.Count OR filterSubstrings.All(fs => resourceSubstrings.Contains(fs)). Also you don't need to compute the filterSubstring in every iteration, they do not change. so put them out of your loop.

– Orel Eraki
Nov 16 '18 at 19:05

|
show 2 more comments

So I'm working on a filter for a resource list and one of the filters is the Name property(string).

As a(dumb) example : resource name is "Big,Red/Square Table" and the filter is "Table Red", it should be a valid resource

This is what I could come up with using the little time I had:

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter) || filter == "") return;

    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var validResources = new List<ResourceModel>();



    foreach (var resource in model.ResourcesViewModel.Resources)

    {

        var filterSubstrings =

            filter

            .ToLower()

            .Split(separators)

            .ToList();



        var resourceSubstrings =

            resource.Name

            .ToLower()

            .Split(separators)

            .ToList();



        resourceSubstrings.ForEach(substring => {

            if (filterSubstrings.Contains(substring))

                filterSubstrings.RemoveAll(sub => sub == substring);

        });



        if (filterSubstrings.Count == 0)

            validResources.Add(resource);

    }



    model.ResourcesViewModel.Resources = validResources;

}

Should I take a different approach for this?

EDIT:
Ended up going with this until I figure out RegEx

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter)) return;



    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var filterSubstrings =

        filter

            .ToLower()

            .Split(separators)

            .ToList();



    var validResources = model.ResourcesViewModel.Resources

        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

        .ToList();



    model.ResourcesViewModel.Resources = validResources;

}

edited Nov 20 '18 at 9:12

asked Nov 16 '18 at 18:41

Xeyth

606

3

Yeah. Definitely look towards a regex solution - you'll definitely have more concise code. There are other ways to skin this cat, but you'd have to be digging back to your comp sci 101 past and thinking about dynamic programming (at least that's what's coming to my mind, LOL). Single responsibility principle based approach also might make your life a lesser hell, here, as well. In both the regex and non-regex approaches, try to leverage an immutability based approach. You're going to really appreciate that you didn't change things in-place, later on.

– code4life
Nov 16 '18 at 18:49

I haven't used too much RegEx though, I know it's damn powerful. Is there a way to generate proper regex patterns based on ones input?

– Xeyth
Nov 16 '18 at 18:56

1

@Xeyth, To add on code4life excellent comment. I will also clarify, about specific point, if the method you are working with, only need the resource list, you do not want to let the method "know" all of your object and his hierarchy. some of the reasons for that is: in case the hierarchy will change, or you will want to use this logic in some other part of your application. you don't need to pass things that the method doesn't care, nor should you.

– Orel Eraki
Nov 16 '18 at 18:57

@Xeyth: absolutely. If you're using .NET 4.5 or higher, it gets even easier since you get to leverage string interpolation. For instance, $"{your variable here}regex expression here" - that's just a very raw, off-the-cuff example. I strongly suggest googling regex, you are not going to need a very complex regex, for what you are trying to do.

– code4life
Nov 16 '18 at 18:59

1

@Xeyth, If you only wants to "beautify" your method, you can work with .Intersect or .All, which is immutable and also, almost gives you the solution. e.g: filterSubstrings.Intersect(resourceSubstrings).Count() == filterSubstrings.Count OR filterSubstrings.All(fs => resourceSubstrings.Contains(fs)). Also you don't need to compute the filterSubstring in every iteration, they do not change. so put them out of your loop.

– Orel Eraki
Nov 16 '18 at 19:05

|
show 2 more comments

So I'm working on a filter for a resource list and one of the filters is the Name property(string).

As a(dumb) example : resource name is "Big,Red/Square Table" and the filter is "Table Red", it should be a valid resource

This is what I could come up with using the little time I had:

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter) || filter == "") return;

    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var validResources = new List<ResourceModel>();



    foreach (var resource in model.ResourcesViewModel.Resources)

    {

        var filterSubstrings =

            filter

            .ToLower()

            .Split(separators)

            .ToList();



        var resourceSubstrings =

            resource.Name

            .ToLower()

            .Split(separators)

            .ToList();



        resourceSubstrings.ForEach(substring => {

            if (filterSubstrings.Contains(substring))

                filterSubstrings.RemoveAll(sub => sub == substring);

        });



        if (filterSubstrings.Count == 0)

            validResources.Add(resource);

    }



    model.ResourcesViewModel.Resources = validResources;

}

Should I take a different approach for this?

EDIT:
Ended up going with this until I figure out RegEx

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter)) return;



    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var filterSubstrings =

        filter

            .ToLower()

            .Split(separators)

            .ToList();



    var validResources = model.ResourcesViewModel.Resources

        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

        .ToList();



    model.ResourcesViewModel.Resources = validResources;

}

edited Nov 20 '18 at 9:12

asked Nov 16 '18 at 18:41

Xeyth

606

So I'm working on a filter for a resource list and one of the filters is the Name property(string).

As a(dumb) example : resource name is "Big,Red/Square Table" and the filter is "Table Red", it should be a valid resource

This is what I could come up with using the little time I had:

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter) || filter == "") return;

    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var validResources = new List<ResourceModel>();



    foreach (var resource in model.ResourcesViewModel.Resources)

    {

        var filterSubstrings =

            filter

            .ToLower()

            .Split(separators)

            .ToList();



        var resourceSubstrings =

            resource.Name

            .ToLower()

            .Split(separators)

            .ToList();



        resourceSubstrings.ForEach(substring => {

            if (filterSubstrings.Contains(substring))

                filterSubstrings.RemoveAll(sub => sub == substring);

        });



        if (filterSubstrings.Count == 0)

            validResources.Add(resource);

    }



    model.ResourcesViewModel.Resources = validResources;

}

Should I take a different approach for this?

EDIT:
Ended up going with this until I figure out RegEx

static void ApplyNameFilter(ref ApplicationViewModel model, string filter)

{

    if (string.IsNullOrEmpty(filter)) return;



    char separators = {' ', ',', '.', '/', '\', '|', '_', '-'};

    var filterSubstrings =

        filter

            .ToLower()

            .Split(separators)

            .ToList();



    var validResources = model.ResourcesViewModel.Resources

        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

        .ToList();



    model.ResourcesViewModel.Resources = validResources;

}

c# string search

edited Nov 20 '18 at 9:12

asked Nov 16 '18 at 18:41

Xeyth

606

edited Nov 20 '18 at 9:12

asked Nov 16 '18 at 18:41

Xeyth

606

edited Nov 20 '18 at 9:12

asked Nov 16 '18 at 18:41

Xeyth

606

asked Nov 16 '18 at 18:41

Xeyth

606

asked Nov 16 '18 at 18:41

Xeyth

606

3

Yeah. Definitely look towards a regex solution - you'll definitely have more concise code. There are other ways to skin this cat, but you'd have to be digging back to your comp sci 101 past and thinking about dynamic programming (at least that's what's coming to my mind, LOL). Single responsibility principle based approach also might make your life a lesser hell, here, as well. In both the regex and non-regex approaches, try to leverage an immutability based approach. You're going to really appreciate that you didn't change things in-place, later on.

– code4life
Nov 16 '18 at 18:49

I haven't used too much RegEx though, I know it's damn powerful. Is there a way to generate proper regex patterns based on ones input?

– Xeyth
Nov 16 '18 at 18:56

1

@Xeyth, To add on code4life excellent comment. I will also clarify, about specific point, if the method you are working with, only need the resource list, you do not want to let the method "know" all of your object and his hierarchy. some of the reasons for that is: in case the hierarchy will change, or you will want to use this logic in some other part of your application. you don't need to pass things that the method doesn't care, nor should you.

– Orel Eraki
Nov 16 '18 at 18:57

@Xeyth: absolutely. If you're using .NET 4.5 or higher, it gets even easier since you get to leverage string interpolation. For instance, $"{your variable here}regex expression here" - that's just a very raw, off-the-cuff example. I strongly suggest googling regex, you are not going to need a very complex regex, for what you are trying to do.

– code4life
Nov 16 '18 at 18:59

1

@Xeyth, If you only wants to "beautify" your method, you can work with .Intersect or .All, which is immutable and also, almost gives you the solution. e.g: filterSubstrings.Intersect(resourceSubstrings).Count() == filterSubstrings.Count OR filterSubstrings.All(fs => resourceSubstrings.Contains(fs)). Also you don't need to compute the filterSubstring in every iteration, they do not change. so put them out of your loop.

– Orel Eraki
Nov 16 '18 at 19:05

|
show 2 more comments

3

Yeah. Definitely look towards a regex solution - you'll definitely have more concise code. There are other ways to skin this cat, but you'd have to be digging back to your comp sci 101 past and thinking about dynamic programming (at least that's what's coming to my mind, LOL). Single responsibility principle based approach also might make your life a lesser hell, here, as well. In both the regex and non-regex approaches, try to leverage an immutability based approach. You're going to really appreciate that you didn't change things in-place, later on.

– code4life
Nov 16 '18 at 18:49

I haven't used too much RegEx though, I know it's damn powerful. Is there a way to generate proper regex patterns based on ones input?

– Xeyth
Nov 16 '18 at 18:56

1

@Xeyth, To add on code4life excellent comment. I will also clarify, about specific point, if the method you are working with, only need the resource list, you do not want to let the method "know" all of your object and his hierarchy. some of the reasons for that is: in case the hierarchy will change, or you will want to use this logic in some other part of your application. you don't need to pass things that the method doesn't care, nor should you.

– Orel Eraki
Nov 16 '18 at 18:57

@Xeyth: absolutely. If you're using .NET 4.5 or higher, it gets even easier since you get to leverage string interpolation. For instance, $"{your variable here}regex expression here" - that's just a very raw, off-the-cuff example. I strongly suggest googling regex, you are not going to need a very complex regex, for what you are trying to do.

– code4life
Nov 16 '18 at 18:59

1

@Xeyth, If you only wants to "beautify" your method, you can work with .Intersect or .All, which is immutable and also, almost gives you the solution. e.g: filterSubstrings.Intersect(resourceSubstrings).Count() == filterSubstrings.Count OR filterSubstrings.All(fs => resourceSubstrings.Contains(fs)). Also you don't need to compute the filterSubstring in every iteration, they do not change. so put them out of your loop.

– Orel Eraki
Nov 16 '18 at 19:05

Yeah. Definitely look towards a regex solution - you'll definitely have more concise code. There are other ways to skin this cat, but you'd have to be digging back to your comp sci 101 past and thinking about dynamic programming (at least that's what's coming to my mind, LOL). Single responsibility principle based approach also might make your life a lesser hell, here, as well. In both the regex and non-regex approaches, try to leverage an immutability based approach. You're going to really appreciate that you didn't change things in-place, later on.

– code4life
Nov 16 '18 at 18:49

I haven't used too much RegEx though, I know it's damn powerful. Is there a way to generate proper regex patterns based on ones input?

– Xeyth
Nov 16 '18 at 18:56

@Xeyth, To add on code4life excellent comment. I will also clarify, about specific point, if the method you are working with, only need the resource list, you do not want to let the method "know" all of your object and his hierarchy. some of the reasons for that is: in case the hierarchy will change, or you will want to use this logic in some other part of your application. you don't need to pass things that the method doesn't care, nor should you.

– Orel Eraki
Nov 16 '18 at 18:57

@Xeyth: absolutely. If you're using .NET 4.5 or higher, it gets even easier since you get to leverage string interpolation. For instance, $"{your variable here}regex expression here" - that's just a very raw, off-the-cuff example. I strongly suggest googling regex, you are not going to need a very complex regex, for what you are trying to do.

– code4life
Nov 16 '18 at 18:59

@Xeyth, If you only wants to "beautify" your method, you can work with .Intersect or .All, which is immutable and also, almost gives you the solution. e.g: filterSubstrings.Intersect(resourceSubstrings).Count() == filterSubstrings.Count OR filterSubstrings.All(fs => resourceSubstrings.Contains(fs)). Also you don't need to compute the filterSubstring in every iteration, they do not change. so put them out of your loop.

– Orel Eraki
Nov 16 '18 at 19:05

|
show 2 more comments

1 Answer
1

active

oldest

votes

You can use LINQ to make this more concise (and probably faster, as you are creating Lists and removing elements over every resource unnecessarily, though a non-LINQ solution could be even faster).

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => {

                            var resourceSubstrings = resource.Name.ToLower().Split(separators).ToHashSet();

                            return filterSubstrings.All(fs => resourceSubstrings.Contains(fs));

                        })

                        .ToList();

If you are willing to accept all the filter substrings being inside the Name regardless of the separators, then you can simplify to just be:

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

                        .ToList();

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

add a comment |

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1 Answer
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1 Answer
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oldest

votes

You can use LINQ to make this more concise (and probably faster, as you are creating Lists and removing elements over every resource unnecessarily, though a non-LINQ solution could be even faster).

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => {

                            var resourceSubstrings = resource.Name.ToLower().Split(separators).ToHashSet();

                            return filterSubstrings.All(fs => resourceSubstrings.Contains(fs));

                        })

                        .ToList();

If you are willing to accept all the filter substrings being inside the Name regardless of the separators, then you can simplify to just be:

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

                        .ToList();

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

add a comment |

You can use LINQ to make this more concise (and probably faster, as you are creating Lists and removing elements over every resource unnecessarily, though a non-LINQ solution could be even faster).

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => {

                            var resourceSubstrings = resource.Name.ToLower().Split(separators).ToHashSet();

                            return filterSubstrings.All(fs => resourceSubstrings.Contains(fs));

                        })

                        .ToList();

If you are willing to accept all the filter substrings being inside the Name regardless of the separators, then you can simplify to just be:

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

                        .ToList();

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

add a comment |

You can use LINQ to make this more concise (and probably faster, as you are creating Lists and removing elements over every resource unnecessarily, though a non-LINQ solution could be even faster).

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => {

                            var resourceSubstrings = resource.Name.ToLower().Split(separators).ToHashSet();

                            return filterSubstrings.All(fs => resourceSubstrings.Contains(fs));

                        })

                        .ToList();

If you are willing to accept all the filter substrings being inside the Name regardless of the separators, then you can simplify to just be:

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

                        .ToList();

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

You can use LINQ to make this more concise (and probably faster, as you are creating Lists and removing elements over every resource unnecessarily, though a non-LINQ solution could be even faster).

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => {

                            var resourceSubstrings = resource.Name.ToLower().Split(separators).ToHashSet();

                            return filterSubstrings.All(fs => resourceSubstrings.Contains(fs));

                        })

                        .ToList();

If you are willing to accept all the filter substrings being inside the Name regardless of the separators, then you can simplify to just be:

var validResources = model.ResourcesViewModel.Resources

                        .Where(resource => filterSubstrings.All(fs => resource.Name.ToLower().Contains(fs)))

                        .ToList();

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

answered Nov 16 '18 at 20:32

NetMage

13.3k11935

add a comment |

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