rspec/rules/S1155/csharp/rule.adoc

Using `.Count()` to test for emptiness works, but using `.Any()` makes the intent clearer, and the code more readable. However, there are some cases where special attention should be paid:

* if the collection is an `EntityFramework` or other ORM query, calling `.Count()` will cause executing a potentially massive SQL query and could put a large overhead on the application database. Calling `.Any()` will also connect to the database, but will generate much more efficient SQL.
* if the collection is part of a LINQ query that contains `.Select()` statements that create objects, a large amount of memory could be unnecessarily allocated. Calling `.Any()` will be much more efficient because it will execute fewer iterations of the enumerable.

== Noncompliant Code Example

[source,csharp]
----
private static bool HasContent(IEnumerable<string> strings)
{
  return strings.Count() > 0;  // Noncompliant
}

private static bool HasContent2(IEnumerable<string> strings)
{
  return strings.Count() >= 1;  // Noncompliant
}

private static bool IsEmpty(IEnumerable<string> strings)
{
  return strings.Count() == 0;  // Noncompliant
}
----

== Compliant Solution

[source,csharp]
----
private static bool HasContent(IEnumerable<string> strings)
{
  return strings.Any();
}

private static bool HasContent2(IEnumerable<string> strings)
{
  return strings.Any();
}

private static bool IsEmpty(IEnumerable<string> strings)
{
  return !strings.Any();
}
----

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== Implementation Specification
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== Comments And Links
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