rspec/rules/S3456/csharp/rule.adoc

== Why is this an issue?

`ToCharArray` can be omitted when the operation on the array could have been done directly on the string, such as when iterating over the characters in a string, and when accessing a character in a string via an array index. In those cases, explicit `ToCharArray` calls should be omitted.

C#11 introduced support for UTF-8 string literals, which are stored as `ReadOnlySpan<byte>` objects.
For that reason, the rule also raises on `ToArray` invocations of `ReadOnlySpan<T>`.

=== Noncompliant code example

[source,csharp]
----
string str = "some string";
foreach (var c in str.ToCharArray()) // Noncompliant
{
  // ...    
}

ReadOnlySpan<byte> span = "some UTF-8 string literal"u8;
foreach (var c in span.ToArray()) // Noncompliant
{
  // ...    
}
----


=== Compliant solution

[source,csharp]
----
string str = "some string";
foreach (var c in str)
{
  // ...    
}

ReadOnlySpan<byte> span = "some UTF-8 string literal"u8;
foreach (var b in span) // Compliant 
{
  // ...    
}
----


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== Comments And Links
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