Partial string matching in LINQ

Question

Consider following SQL statement -

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

This is will search for customers having 'IS' as part of first name, right?

I like the same statement to be in LINQ -

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

I am unable to specify that condition. Can anybody help me out solve this.

Thanks for sharing your time and wisdom.

Answer 1

Most LINQ -> SQL translators will take a few regular methods from c# and translate them into SQL. Contains is a very common method to translate and works 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;

Answer 2

For Case insenstive contains, you can either convert the string to same case (lower or upper) or its 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;

Although the performance gain may be negligible from this method, but it will ensure a proper case insensitive comparison. Its always a good practice to use StringComparison enum for case insensitive string comparison. You may see: The Turkish İ Problem and Why You Should Care