rspec/rules/S3247/csharp/rule.adoc

Because the ``++is++`` operator performs a cast if the object is not null, using ``++is++`` to check type and then casting the same argument to that type, necessarily performs two casts. The same result can be achieved more efficiently with a single cast using ``++as++``, followed by a null-check.


== Noncompliant Code Example

[source,csharp]
----
if (x is Fruit)  // Noncompliant
{
  var f = (Fruit)x; // or x as Fruit
  // ...
}
----


== Compliant Solution

[source,csharp]
----
// C# 6
var f = x as Fruit;
if (f != null)
{
  // ...
}
// C# 7
if (x is Fruit fruit)
{
  // ...
}
----


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== Implementation Specification
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== Comments And Links
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