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Partial string matching in LINQ

Consider the following SQL statement -

SELECT * FROM Customers WHERE FirstName LIKE '%IS%'

It will be looking for clients with "IS" as part of the name, right?

I like the same statement as in LINQ -

var names = from cust in customers where cust.FirstName ......

I cannot specify this condition. Can someone help me solve this.

Thank you for sharing your time and wisdom.

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3 answers


Most LINQ -> SQL translators will take a few regular methods from C # and translate them to SQL. Contains a very common method for translating and working with linq2sql and EF

var names = from cust in customers 
            where cust.FirstName.Contains("IS")
            select cust;


EDIT: (case insensitive)

var names = from cust in customers 
            where cust.FirstName.ToLower().Contains("is")
            select cust;
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For the insenstive case, contains

you can either convert the string to the same case (lower or upper), or better if you can use String.IndexOf Method (String, StringComparison)

var names = from cust in customers 
            where cust.FirstName.IndexOf("IS",StringComparison.InvariantCultureIgnoreCase) >= 0
            select cust;


While the performance gain may be negligible from this method, it will provide a correct case-insensitive comparison. It's always a good StringComparison

idea to use enum for case-insensitive string comparisons. You can see: The Turkish problem and why you should care

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Try the following:

var names = from cust in customers where cust.FirstName.Contains("IS")
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