Why Choose `Dictionary` over `Hashtable` in C#?
Why is Dictionary<TKey, TValue>
more popular than Hashtable
in C#?
In C#, programmers generally prefer to use Dictionary<TKey, TValue>
types instead of Hashtable
classes. This preference stems from several key advantages provided by Dictionary<TKey, TValue>
.
First of all, Dictionary<TKey, TValue>
is a generic type, while Hashtable
is not. This means that Dictionary<TKey, TValue>
provides compile-time type safety. When using Dictionary<TKey, TValue>
, the compiler ensures that only numeric values of the specified type can be inserted into the dictionary, thus preventing potential runtime errors caused by type mismatches.
Additionally, Dictionary<TKey, TValue>
provides a type-safe way to retrieve values stored in a dictionary. In contrast, Hashtable
requires a cast on the retrieved value, which is error-prone and tedious.
It is worth noting that the Dictionary<TKey, TValue>
implementation in .NET is based on Hashtable
, as evidenced by comments in its source code. However, the generic nature of Dictionary<TKey, TValue>
and its built-in type safety make it a more convenient and reliable choice in most cases, which explains why it is more popular than Hashtable
in C#.
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