在LINQ查詢中調用ToList（）或ToArray（）更好嗎？ - Is it better to call ToList() or ToArray() in LINQ queries?

問題：

I often run into the case where I want to eval a query right where I declare it.我經常遇到我想在聲明它的地方評估一個查詢的情況。 This is usually because I need to iterate over it multiple times and it is expensive to compute.這通常是因爲我需要對其進行多次遍歷，並且計算起來很昂貴。 For example:例如：

string raw = "...";
var lines = (from l in raw.Split('\n')
             let ll = l.Trim()
             where !string.IsNullOrEmpty(ll)
             select ll).ToList();

This works fine.這很好。 But if I am not going to modify the result, then I might as well call ToArray() instead of ToList() .但是，如果我不打算修改結果，那麼我不妨調用ToArray()而不是ToList() 。

I wonder however whether ToArray() is implemented by first calling ToList() and is therefore less memory efficient than just calling ToList() .但是我不知道ToArray()是否通過首先調用ToList() ToArray()來實現，因此與僅調用ToList()相比，內存效率較低。

Am I crazy?我瘋了嗎？ Should I just call ToArray() - safe and secure in the knowledge that the memory won't be allocated twice?我應該只調用ToArray() －在不會兩次分配內存的情況下安全可靠嗎？

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解決方案：

參考一： https://stackoom.com/question/4diY
參考二： Is it better to call ToList() or ToArray() in LINQ queries?