Great job — we just covered a lot of LINQ! Here’s a recap:
- LINQ is a set of language and framework features for writing structured, type-safe queries over local object collections and remote data sources.
- Use LINQ by referencing the
System.Linqnamespace in your file.
- When a LINQ query returns a sequence of elements its type is
IEnumerable<T>. That means it works with
foreachloops and its length is accessible with
- Store a query’s result in a variable of type
varis an implicit type, meaning it gets all of the benefits of type-checking without our specifying the actual type.
- LINQ queries can be written in method syntax or query syntax.
- We prefer method syntax for single operations and query syntax for most everything else.
Whereoperator is used to select certain elements from a sequence.
Selectoperator determines what is returned for each element in the sequence.
fromoperator declares a range variable that is used to traverse the sequence.
- LINQ can be used on arrays and lists, among other datatypes.
If you’re curious or want more practice, here are some additional resources:
- Learn more by reading Microsoft’s guide to LINQ.
- Find a list of keywords for query syntax here.
- Find a list of common methods for method syntax here.
- Find a complete list of methods for
There are a few bugs in this code! Fix each one before moving on.
Take this course for free