in_array（）無法正常運行

-1

可能重複：
!in_array use in PHP - conditional statments in_array（）無法正常運行

我有這樣的代碼，做相反。

假設我有1,2,3,3,4,5

while ($row = mysql_fetch_assoc($result)) { 

    $item = $row['item']; 
    echo $item . '<br />'; // for testing 
    $items[] = $row['item']; 
    if (!in_array($item, $items)) { 

     $output[] = $row; 

     foreach ($items as $item) { 
      echo 'Array thus far: ' . $item . '<br />'; // for testing 
     } 
    } 

}

陣列基本上我想在數組中沒有重複。測試代碼應該最終打印1,2,3,4,5 ..但它實際上打印出1,2,3,3,4,5 in_array（）函數似乎不工作在這裏與變量？

這裏是真正的輸出：

Avengers 
Array thus far: Avengers 
Avengers 
Array thus far: Avengers 
Array thus far: Avengers 
American Dad! 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
American Dad! 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Christopher Columbus 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Avatar 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Kung Pao Chicken 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
The Brak Show 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Avengers 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
The Brak Show 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
Array thus far: The Brak Show 
Space Ghost: Coast to Coast 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
Array thus far: The Brak Show 
Array thus far: Space Ghost: Coast to Coast 
Battlestar Galactica (2004) 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
Array thus far: The Brak Show 
Array thus far: Space Ghost: Coast to Coast 
Array thus far: Battlestar Galactica (2004) 
Potstickers 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
Array thus far: The Brak Show 
Array thus far: Space Ghost: Coast to Coast 
Array thus far: Battlestar Galactica (2004) 
Array thus far: Potstickers 
Potstickers 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
Array thus far: The Brak Show 
Array thus far: Space Ghost: Coast to Coast 
Array thus far: Battlestar Galactica (2004) 
Array thus far: Potstickers 
Array thus far: Potstickers 
Avatar 
Array thus far: Avengers 
Array thus far: Avengers 
Array thus far: American Dad! 
Array thus far: American Dad! 
Array thus far: Christopher Columbus 
Array thus far: Avatar 
Array thus far: Kung Pao Chicken 
Array thus far: The Brak Show 
Array thus far: Avengers 
Array thus far: The Brak Show 
Array thus far: Space Ghost: Coast to Coast 
Array thus far: Battlestar Galactica (2004) 
Array thus far: Potstickers 
Array thus far: Potstickers 
Array thus far: Avatar

有在這裏重複的項目，我想保持了陣。

來源

2012-10-04 KickingLettuce

@KickingLettuce：爲什麼你再次問同樣的問題？（感謝jeroen的領導） – Jon

你需要按$row['item']到$items你做後in_array()：

while ($row = mysql_fetch_assoc($result)) { 
    $item = $row['item']; 
    echo $item . '<br />'; // for testing 
    if (!in_array($item, $items)) { 
     $output[] = $row; 
     foreach ($items as $item) { 
      echo 'Array thus far: ' . $item . '<br />'; // for testing 
     } 
     $items[] = $row['item']; 
    } 
}

或者您也可以通過刪除$items簡化它：

while ($row = mysql_fetch_assoc($result)) { 
    $item = $row['item']; 
    echo $item . '<br />'; // for testing 
    if (!in_array($item, $output)) { 
     $output[] = $row; 
     foreach ($items as $item) { 
      echo 'Array thus far: ' . $item . '<br />'; // for testing 
     } 
    } 
}

來源

2012-10-04 21:56:48

這工作謝謝！我正在按順序做事。 – KickingLettuce

你守着插入到$output，但你實際打印$items未在所有受保護。

還要考慮到，根據結果集的預期大小和可能的重複百分比，允許重複項然後用array_unique進行篩選可能會快得多（這將需要額外的內存並且可以被認爲是經典的時間/空間折衷）。

來源

2012-10-04 21:56:42 Jon

in_array（）無法正常運行

回答

相關問題