两个注意事项未定义变量where和search

Question

Notice: Undefined variable: where
Notice: Undefined variable: search

我在所有页面上都收到了这两条通知。

我该如何解决这些问题？

刚刚添加了输入类型。

<input type="text" name="search" value="<?= $search; ?>" />
<input type="submit" name="submit" value="search" />

<?php
if (!isset($page)) {
    $page = 1;
}
$view = 50;
$start = ($view * $page) - $view;
//
if (isset($search)) {    
    $where = "WHERE `first` LIKE '%$search%' OR `second` LIKE '%$search%'";
} 
$i = 0;    
$query = mysql_query("SELECT `first`, `second` FROM `table_one` $where ORDER BY `id` ASC LIMIT $start, $view");
while ($row = mysql_fetch_object($query)) {
?>

Answer 1

if (isset($search)) {    
    $where = "WHERE `first` LIKE '%$search%' OR `second` LIKE '%$search%'";
}

此部分需要else语句或$where需要具有默认值。如果未设置$search，则永远不会设置$where。

$where = "";
if (isset($search)) {    
    $where = "WHERE `first` LIKE '%$search%' OR `second` LIKE '%$search%'";
}