AnyCase Searching Using LINQ

Question

I have a LINQ statement as follows:

myList = MyList.Where(x => 
    x.Name.Contains(SearchValue) ||
    x.Address.Contains(SearchValue)).ToList();

My Database can have upper or lower cases for the Name field like 'VSTS' or 'vsts'
I want my LINQ statement to execute with any case.

In the above LINQ statement if i provide with lower case values and the database is having upper case, the searching fails.. which i don't want.

Is this actually in LINQ to Objects, or a database-oriented provider? — Jon Skeet, Feb 12 '13 at 10:42
its Linq to Objects, I have extracted the values from the database prior executing My linq statement. — tsvsdev, Feb 12 '13 at 10:45
Possible duplicate: http://stackoverflow.com/questions/444798/case-insensitive-containsstring/444813#444813 .. Have you even tried to use google, before asking the question? — mipe34, Feb 12 '13 at 11:01
yup i did.. but possible my keywords didn't matched to get the Link..i needed it on urgent basis.. — tsvsdev, Feb 12 '13 at 11:09

score 5 · Accepted Answer · answered Feb 12 '13 at 10:49

The best option would be using the ordinal case-insensitive comparison, however the Contains method does not support it, so your other option would be to use string.IndexOf.

It would be better to wrap this in an extension method, such as:

public static bool Contains(this string target, string value, StringComparison comparison)
{
    return target.IndexOf(value, comparison) >= 0;
}

So you could use:

myList.Where(x => x.Name.Contains(SearchValue, StringComparison.OrdinalIgnoreCase) ||
                  x.Address.Contains(SearchValue, StringComparison.OrdinalIgnoreCase));

Akram Shahda · Answer 2 · 2013-02-12T11:03:18.430

1

Use the following:

myList = MyList.Where(x => 
    x.Name.ToUpper(CultureInfo.InvariantCulture).Contains(
        SearchValue.ToUpper(CultureInfo.InvariantCulture)) || 
    x.Address.ToUpper(CultureInfo.InvariantCulture).Contains(
        SearchValue.ToUpper(CultureInfo.InvariantCulture))).
    ToList();

edited Feb 12 '13 at 11:03

answered Feb 12 '13 at 10:44

Akram Shahda

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Normalizing should be made to Upper case. http://msdn.microsoft.com/en-us/library/bb386042.aspx – Jean Hominal Feb 12 '13 at 10:56

JMan · Answer 3 · 2013-02-12T10:47:24.820

0

Try this:

myList = MyList.Where(x => 
    x.Name.ToLower().Contains(SearchValue.ToLower()) || 
    x.Address.ToLower().Contains(SearchValue.ToLower())).ToList();

Check if this works for Linq2Entity, could be the tolower fails :p

edited Feb 12 '13 at 10:47

answered Feb 12 '13 at 10:43

JMan

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Normalizing should be made to Upper case. http://msdn.microsoft.com/en-us/library/bb386042.aspx – Jean Hominal Feb 12 '13 at 10:57

score 0 · Answer 4 · answered Feb 12 '13 at 10:47

0

you may try the ToLower():

myList = MyList.Where(x => x.Name.ToLower().Contains(SearchValue.ToLower()) 
    || x.Address.ToLower().Contains(SearchValue.ToLower())).ToList();

answered Feb 12 '13 at 10:47

the_joric

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Normalizing should be made to Upper case. http://msdn.microsoft.com/en-us/library/bb386042.aspx – Jean Hominal Feb 12 '13 at 10:58

score 0 · Answer 5 · answered Feb 12 '13 at 10:49

If you need to use Contains() try this:

var svUP = SearchValue.ToUpper();
myList = MyList.Where(x => x.Name.ToUpper().Contains(svUP ) || x.Address.ToUpper().Contains(svUP )).ToList();

But if your fields contains full search value and only problem is casing then you should use Equals() with StingComparison instead:

myList = MyList.Where(x => x.Name.Equals(SearchValue, StringComparison.InvariantCultureIgnoreCase) || x.Address.Equals(SearchValue, StringComparison.InvariantCultureIgnoreCase)).ToList();

Best to use `ToUpperInvariant()` instead of `ToUpper()` =) – J. Steen Feb 12 '13 at 10:51 — J. Steen, Feb 12 '13 at 10:51

AnyCase Searching Using LINQ

5 Answers5