Dictionary looked up twice (CA1854)

Key dotnet.performance.double-dictionary-lookup · Severity info · Category performance

Microsoft analyzer CA1854. Flags ContainsKey followed by the indexer on the same key - two lookups where TryGetValue does one.

Incorrect

if (cache.ContainsKey(key))
    return cache[key];

Correct

if (cache.TryGetValue(key, out var value))
    return value;