In what situations would I specify operation as unchecked?
For example:
int value = Int32.M开发者_如何学JAVAaxValue;
unchecked
{
value += 1;
}
In what ways would this be useful? can you think of any?
Use unchecked
when:
- You want to express a constant via overflow (this can be useful when specifying bit patterns)
- You want arithmetic to overflow without causing an error
The latter is useful when computing a hash code - for example, in Noda Time the project is built with checked arithmetic for virtual everything apart from hash code generation. When computing a hash code, it's entirely normal for overflow to occur, and that's fine because we don't really care about the result as a number - we just want it as a bit pattern, really.
That's just a particularly common example, but there may well be other times where you're really happy for MaxValue + 1
to be MinValue
.
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