Regex in LINQ query

Question

I have a LINQ query like this:

var query = from s in persons
            where (string.IsNullOrEmpty(name) || s.Name.trim().contains(name)) &&
                  (string.IsNullOrEmpty(email) || s.Email.contains(email)) &&
                  (string.IsNullOrEmpty(zip) || s.Zip == zip)
            select s;
			

The name field s coming from the user who can type the name on the web page and then I need to search the persons table for that particular name. Unfortunately, the name First Name and Last name are in the same column in the database and the other issue is there are two spaces and sometimes three spaces between first Name and Last Name so for e.g. if the name is Steve Ramsey. the name in the database is this way:

Steve  Ramsey

or if the name is Steve Ramsey last

It can be stored in the database like this:

Steve   Ramsey Last

Not all the names are stored this way, only few names are like this. I have the Regex to eliminate one/ two extra space:

Regex regex = new Regex("[ ]{2,}", options);
CustName = regex.Replace(CustName, " ");
or
myString = Regex.Replace(myString, @"\s+", " ");

I am not sure how to put this regex in LINQ query.

Any help will be greatly appreciated.

Answer 1

Hi @Anjali Agarwal

how to put this regex in LINQ query.

To put the regex in the LINQ query, you need to convert the persons as Enumerable or List, using the AsEnumerable, AsAsyncEnumerable, ToList, or ToListAsync methods.

Refer to the following sample:

            var name = "Steve Ramsey"; //one space
             
            var query = (from s in _dbcontext.Persons.AsEnumerable()
                        where (Regex.Replace(s.Name, @"\s+", " ").Contains(name))
                        select s).ToList();

The result as below:

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