比较基础的php面试题及答案-填空题

填空题:
1.在PHP中，当前脚本的名称(不包括路径和查询字符串)记录在预定义变量__$_SERVER[PHP_SELF]__中;而链接到当前页面的URL记录在预定义变量__$_SERVER[HTTP_REFERER]__

中

2.执行程序段将输出__0__。

3.在HTTP 1.0中，状态码 401 的含义是____;如果返回“找不到文件”的提示，则可用 header 函数，其语句为____。

4.数组函数 arsort 的作用是__对数组进行逆向排序并保持索引关系__;语句 error_reporting(2047)的作用是__报告所有错误和警告__。

5.PEAR中的数据库连接字符串格式是____。

6.写出一个正则表达式，过虑网页上的所有JS/VBS脚本(即把scrīpt标记及其内容都去掉):preg_replace(“//si”, “newinfo”, $script);

7.以Apache模块的方式安装PHP，在文件http.conf中首先要用语句____动态装载PHP模块，然后再用语句____使得Apache把所有扩展名为php的文件都作为PHP脚本处理。
LoadModule php5_module “c:/php/php5apache2.dll” , AddType application/x-httpd-php .php,

8.语句 include 和 require 都能把另外一个文件包含到当前文件中，它们的区别是____;为了避免多次包含同一文件，可以用语句__require_once||include_once__来代替它们。

9.类的属性可以序列化后保存到 session 中，从而以后可以恢复整个类，这要用到的函数是____。

10.一个函数的参数不能是对变量的引用，除非在php.ini中把__allow_call_time_pass_reference boolean__设为on.

11.SQL中LEFT JOIN的含义是__自然左外链接__。如果 tbl_user记录了学生的姓名(name)和学号(ID)，tbl_score记录了学生(有的学生考试以后被开除了，没有其记录)的学号(ID)

和考试成绩(score)以及考试科目(subject)，要想打印出各个学生姓名及对应的的各科总成绩，则可以用SQL语句____。

12.在PHP中，heredoc是一种特殊的字符串，它的结束标志必须____。

编程题:
13.写一个函数，能够遍历一个文件夹下的所有文件和子文件夹。
答:
function my_scandir($dir)
{
$files = array();
if ( $handle = opendir($dir) ) {
while ( ($file = readdir($handle)) !== false ) {
if ( $file != “..” && $file != “.” ) {
if ( is_dir($dir . “/” . $file) ) {
$files[$file] = scandir($dir . “/” . $file);
}else {
$files[] = $file;
}
}
}
closedir($handle);
return $files;
}
}

14.简述论坛中无限分类的实现原理。
答:
/*
数据表结构如下:
CREATE TABLE `category` (
`categoryID` smallint(5) unsigned NOT NULL auto_increment,
`categoryParentID` smallint(5) unsigned NOT NULL default ’0′,
`categoryName` varchar(50) NOT NULL default ”,
PRIMARY KEY (`categoryID`)
) ENGINE=MyISAM DEFAULT CHARSET=gbk;

INSERT INTO `category` ( `categoryParentID`, `categoryName`) VALUES
(0, ‘一级类别’),
(1, ‘二级类别’),
(1, ‘二级类别’),
(1, ‘二级类别’),
(2, ‘三级类别’),
(2, ’333332′),
(2, ’234234′),
(3, ‘aqqqqqd’),
(4, ‘哈哈’),
(5, ’66333666′);

*/

//指定分类id变量$category_id,然后返回该分类的所有子类
//$default_category为默认的选中的分类
function Get_Category($category_id = 0,$level = 0, $default_category = 0)
{
global $DB;
$sql = “SELECT * FROM category ORDER BY categoryID DESC”;
$result = $DB->query( $sql );
while ($rows = $DB->fetch_array($result))
{
$category_array[$rows[categoryParentID]][$rows[categoryID]] = array(‘id’ => $rows[categoryID], ‘parent’ => $rows[categoryParentID], ‘name’ => $rows

[categoryName]);
}
if (!isset($category_array[$category_id]))
{
return “”;
}
foreach($category_array[$category_id] AS $key => $category)
{
if ($category[id] == $default_category)
{
echo “ }else
{
echo “ }

if ($level > 0)
{
echo “>” . str_repeat( ” “, $level ) . ” ” . $category[name] . “\n”;
}
else
{
echo “>” . $category[name] . “\n”;
}
Get_Category($key, $level + 1, $default_category);
}
unset($category_array[$category_id]);
}

/*
函数返回的数组格式如下所示:
Array
(
[1] => Array ( [id] => 1 [name] => 一级类别 [level] => 0 [ParentID] => 0 )
[4] => Array ( [id] => 4 [name] => 二级类别 [level] => 1 [ParentID] => 1 )
[9] => Array ( [id] => 9 [name] => 哈哈 [level] => 2 [ParentID] => 4 )
[3] => Array ( [id] => 3 [name] => 二级类别 [level] => 1 [ParentID] => 1 )
[8] => Array ( [id] => 8 [name] => aqqqqqd [level] => 2 [ParentID] => 3 )
[2] => Array ( [id] => 2 [name] => 二级类别 [level] => 1 [ParentID] => 1 )
[7] => Array ( [id] => 7 [name] => 234234 [level] => 2 [ParentID] => 2 )
[6] => Array ( [id] => 6 [name] => 333332 [level] => 2 [ParentID] => 2 )
[5] => Array ( [id] => 5 [name] => 三级类别 [level] => 2 [ParentID] => 2 )
[10] => Array ( [id] => 10 [name] => 66333666 [level] => 3 [ParentID] => 5 )
)
*/
//指定分类id,然后返回数组
function Category_array($category_id = 0,$level=0)
{
global $DB;
$sql = “SELECT * FROM category ORDER BY categoryID DESC”;
$result = $DB->query($sql);
while ($rows = $DB->fetch_array($result))
{
$category_array[$rows[categoryParentID]][$rows[categoryID]] = $rows;
}

foreach ($category_array AS $key=>$val)
{
if ($key == $category_id)
{
foreach ($val AS $k=> $v)
{
$options[$k] =
array(
‘id’ => $v[categoryID], ‘name’ => $v[categoryName], ‘level’ => $level, ‘ParentID’=>$v[categoryParentID]
);

$children = Category_array($k, $level+1);

if (count($children) > 0)
{
$options = $options + $children;
}
}
}
}
unset($category_array[$category_id]);
return $options;
}

?>


class cate
{

function Get_Category($category_id = 0,$level = 0, $default_category = 0)
{
echo $category_id;
$arr = array(
’0′ => array(
’1′ => array(‘id’ => 1, ‘parent’ => 0, ‘name’ => ’1111′),
’2′ => array(‘id’ => 2, ‘parent’ => 0, ‘name’ => ’2222′),
’4′ => array(‘id’ => 4, ‘parent’ => 0, ‘name’ => ’4444′)
),
’1′ => array(
’3′ => array(‘id’ => 3, ‘parent’ => 1, ‘name’ => ’333333′),
’5′ => array(‘id’ => 5, ‘parent’ => 1, ‘name’ => ’555555′)
),

’3′ => array(
’6′ => array(‘id’ => 6, ‘parent’ => 3, ‘name’ => ’66666′),
’7′ => array(‘id’ => 7, ‘parent’ => 3, ‘name’ => ’77777′)
),
’4′ => array(
’8′ => array(‘id’ => 8, ‘parent’ => 4, ‘name’ => ’8888′),
’9′ => array(‘id’ => 9, ‘parent’ => 4, ‘name’ => ’9999′)
)
);

if (!isset($arr[$category_id]))
{
return “”;
}

foreach($arr[$category_id] AS $key => $cate)
{
if ($cate[id] == $default_category)
{
$txt = “ }else{
$txt = “ }

if ($level > 0)
{
$txt1 = “>” . str_repeat( “-”, $level ) . ” ” . $cate[name] . “\n”;
}else{
$txt1 = “>” . $cate[name] . “\n”;
}
$val = $txt.$txt1;
echo $val;
self::Get_Category($key, $level + 1, $default_category);
}

}

function getFlush($category_id = 0,$level = 0, $default_category = 0)
{

ob_start();

self::Get_Category($category_id ,$level, $default_category);

$out = ob_get_contents();

ob_end_clean();
return $out;
}
}
$id =$_GET[id];
echo “”;
$c = new cate();
//$c->Get_Category();
$ttt= $c->getFlush($id,’0′,’3′);
echo $ttt;
echo “”;
?>