With the "classic" method, if the cast fails, an InvalidCastException
is thrown. With the as
method, it results in null
, which can be checked for, and avoid an exception being thrown.
Also, you can only use as
with reference types, so if you are typecasting to a value type, you must still use the "classic" method.
Note:
The as
method can only be used for types that can be assigned a null
value. That use to only mean reference types, but when .NET 2.0 came out, it introduced the concept of a nullable value type. Since these types can be assigned a null
value, they are valid to use with the as
operator.
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