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Correction status：qualified
Teacher's comments：fetchAll()就算取一条, 那也是二维数组, 与fetch()不同
Collection
Collection
把原來存到php array中的數據改為database存放.
1.$sql = 'sql語句'; //設置sql語句
2. $preobj = $pdo->prepare($sql) // 建立預處理對象
3.$preobj->execute(); //執行
4. $arr = $preobj->fetch/fetchAll(PDO::FETCH_ASSOC) //把數據存放到數組中
**個人理解: fetch->用於單維數組, fetchAll->用於多維數組 , fetchAll + SQL語句中使用LIMIT 可做到fetch效果
主要部份修改在header,所以只貼header部份的代碼。
<?php //connect to database first require __DIR__ . '/../db/connect.php'; //get foods data from database $sql = 'SELECT * FROM `foods`'; //prepare $preObj = $pdo->prepare( $sql ); //execute $preObj->execute(); //input to array $foods = $preObj->fetchAll( PDO::FETCH_ASSOC ); //get category data from database $sql = 'SELECT * FROM `category`'; $preObj = $pdo->prepare( $sql ); $preObj->execute(); $cates = $preObj->fetchAll( PDO::FETCH_ASSOC ); //count array length $cate_count = count( $cates ); $sql = 'SELECT * FROM `system` LIMIT 1'; $preObj = $pdo->prepare( $sql ); $preObj->execute(); $system = $preObj->fetch( PDO::FETCH_ASSOC ); //fetchAll ->using in 多維數組, fetch->using in 1維數組 //fetch + LIMIT = fetch ?> <!doctype html> <html lang="en"> <head> <meta charset="UTF-8"> <link rel="stylesheet" href="../css/style.css"> <meta name="description" content="<?php echo $system['desc'] ?>"> <meta name="keywords" content="<?php echo $system['key'] ?>"> <title><?php echo $system['title'] ?></title> </head> <body> <div class="header"> <ul class="nav"> <li><a href="index.php">HomePage</a></li> <?php foreach ( $cates as $cate ) : ?> <li><a href="list.php?cat_id=<?php echo $cate['cat_id']; ?>"><?php echo $cate['alias'] ?></a></li> <?php endforeach; ?> </ul> </div>
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