定義的λ外子查詢迭代變量評價

Question

從LINQ Quiz問題和答案，Q4和Q5

隨着colors陣列的數量爲：

string[] colors = { "green", "brown", "blue", "red" }; 

和查詢從回答到Q4：

var query = 
    from c in colors 
    where c.Length == colors.Max (c2 => c2.Length) 
    select c; 

我是否正確理解外部查詢迭代表達式c2.Length將被評估16次？

即，用於在colors陣列的每個項目с，所述colors.Max (c2 => c2.Length)將被計算一次，即Max()計算將進行4次共i。並且對於每個Max()評估，c2.Length將被發現4次？

Answer 1

是的，這是正確的。易於檢查，以及如果你有LINQPad嘗試：

string[] colors = { "green", "brown", "blue", "red" }; 

int count = 0; 

var query = 
    from c in colors 
    where c.Length == colors.Max (c2 => 
     { 
      count.Dump(); 
      count++; 
      return c2.Length; 
     } 
    ) 
    select c; 

query.Dump();