獲取隨機按鈕

Question

我有按鈕1-2-3 ... 12，我想隨機得到其中4個（不重複），然後給他們一個單一的顏色，例如紅色。我怎樣才能做到這一點？

public Form1() 
    { 
     InitializeComponent(); 

     Button[] LeftArr = new Button[12] { button1, button2, button3, button4, button5, button6, button7, button8, button9, button10, button11, button12 }; 

     int i = 0; 
     for (i = 0; i <= LeftArr.Length; i++) 
     { 
      Random rnd = new Random(); 
      Button ShipHere = rnd.Next(button1, button12); 

      // this is where i'm stuck 
     } 

Answer 1

首先，您要確保在循環的每次迭代中都不要創建新的Random對象。否則，你將最終重複。

Random rnd = new Random(); 

List<Button> randomButtons = new List<Button>(4); 

for (int i = 0;i < 4;++i) 
{ 
    Button chosenButton; 

    // Keep looping until we get a button we haven't already picked 
    do 
    { 
     chosenButton = LeftArr[rnd.Next(0, LeftArr.Length)]; 
    } while (randomButtons.Contains(chosenButton)); 

    randomButtons.Add(chosenButton); 
} 

foreach (Button button in randomButtons) 
    button.BackColor = Color.Red;