<t>It is rare, in reality, that you would want to use an array. Definitely use a List any time you want to add/remove data, since resizing arrays is expensive. If you know the data is fixed length, and you want to micro-optimise for some very specific reason (after benchmarking), then an array may be useful.<br/>
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List offers a lot more functionality than an array (although LINQ evens it up a bit), and is almost always the right choice. Except for params arguments, of course. ;-p<br/>
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As a counter - List is one-dimensional; where-as you have have rectangular (etc) arrays like int[,] or string[,,] - but there are other ways of modelling such data (if you need) in an object model.<br/>
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See also:<br/>
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- How/When to abandon the use of Arrays in c#.net?<br/>
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- Arrays, What's the point?<br/>
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That said, I make a lot of use of arrays in my protobuf-net project; entirely for performance:<br/>
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- it does a lot of bit-shifting, so a
byte[] is pretty much essential for encoding;<br/>
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- I use a local rolling
byte[] buffer which I fill before sending down to the underlying stream (and v.v.); quicker than BufferedStream etc;<br/>
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- it internally uses an array-based model of objects (
Foo[] rather than List), since the size is fixed once built, and needs to be very fast.<br/>
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But this is definitely an exception; for general line-of-business processing, a List wins every time.</t>
