Using the foreach (...) syntax, as well as increasing the index variable inside the loop

Question

When viewing C # code, I often see these patterns:

DataType[] items = GetSomeItems();
OtherDataType[] itemProps = new OtherDataType[items.Length];

int i = 0;
foreach (DataType item in items)
{
    // Do some stuff with item, then finally
    itemProps[i] = item.Prop;
    i++;
}

The for loop loops through the objects in items, but also maintains a counter ( i) to iterate over itemProps. I personally don't like this extra ione hanging around, and instead will probably do something like:

DataType[] items = GetSomeItems();
OtherDataType[] itemProps = new OtherDataType[items.Length];

for (int i = 0; i < items.Length; i++)
{
    // Do some stuff with items[i], then finally
    itemProps[i] = items[i].Prop;
}

Maybe there are some advantages to the first approach, which I do not know about? Is this the result of everyone trying to use this fancy syntax foreach (...)? I'm interested in your opinions on this matter.

Answer 1

If you use C # 3.0, which will be better,

OtherDataType[] itemProps = items.Select(i=>i.Prop).ToArray();

Answer 2

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Answer 3

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Answer 4

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Answer 5

, foreach .

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Answer 6

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Answer 7

Do not forget that some collections do not implement the direct access operator [], and you need to iterate through the IEnumerable interface, which is most easily accessed using foreach ().