Consider rewriting null checks and casts using pattern matching CS-R1056
Anti-pattern
Major
8 months ago
—
8 months old
Use pattern matching when casting
89
90 object o = new Foo();
91 var foo = o as Foo;
92 if (foo != null) 93 {
94 //
95 }
Description
Comparing the result of the as expression with null allows you to check if the conversion operation was successful or not. However, it can be rewritten using the is operator allowing you to collapse the cast operation and the result check, thereby making your code concise and naturally readable.
Bad Practice
var foo = mayBeFoo as Foo;
if (foo == null)
{
// `foo` is not of type `Foo`
}
// Do something with `foo`
Recommended
if (mayBeFoo is not Foo foo)
{
// `foo` is not of type `Foo`
}
// Do something with `foo`