我想说这种方法是不是很常用的非空验证，现在的普遍使用的是javascript来验证非空，但是作为学习php的一些知识点，还是可以看看的。
先来看看commit.php中的方法
<?php
$db = mysql_connect(‘localhost‘,‘root‘,‘Ctrip07185419‘);
mysql_select_db(‘moviesite‘,$db) or die(mysql_error($db));
mysql_query(‘set names "gb2312"‘,$db);
?>
<!--
<html>
<head></head>
<title>Commit</title>
<body>
-->
<?php
switch($_GET[‘action‘])
{
case "add":
{
switch($_GET[‘type‘])
{
case ‘movie‘:
$error = array();
$movie_name = isset($_POST[‘movie_name‘]) ? trim($_POST[‘movie_name‘]) : ‘‘;
if(empty($movie_name))
{
$error[] = urlencode(‘Please enter an movie name‘);
}$movie_type = isset($_POST[‘movie_type‘]) ? trim($_POST[‘movie_type‘]) : ‘‘;
if(empty($movie_type))
{
$error[] = urldecode(‘Please enter an movie type‘);
}$movie_year = isset($_POST[‘movie_year‘]) ? trim($_POST[‘movie_year‘]) : ‘‘;
if(empty($movie_year))
{
$error[] = urldecode(‘Please enter an movie year‘);
}$movie_leadactor = isset($_POST[‘movie_leadactor‘]) ? trim($_POST[‘movie_leadactor‘]) : ‘‘;
if(empty($movie_leadactor))
{
$error[] = urldecode(‘Please enter an movie leadactor‘);
}$movie_director = isset($_POST[‘movie_director‘]) ? trim($_POST[‘movie_director‘]) : ‘‘;
if(empty($movie_director))
{
$error[] = urldecode(‘Please enter an movie director‘);
}$movie_release = isset($_POST[‘movie_release‘]) ? trim($_POST[‘movie_release‘]) : ‘‘;
if(empty($movie_release))
{
$error[] = urldecode(‘Please enter an movie release‘);
}
else if(!preg_match(‘|^\d{2}-\d{2}-\d{4}$|‘ , $movie_release))
{
$error[] = urlencode(‘Please enter a date in dd-mm-yyyy format‘);
}
else
{
list($day, $month, $year) = explode(‘-‘, $movie_release);
if(!checkdate($month , $day , $year))
{
$error[] = urldecode(‘please enter a validate date‘);
}
else
{
$movie_release = mktime(0, 0, 0, $month, $day, $year);
}
}$movie_rating = isset($_POST[‘movie_rating‘]) ? trim($_POST[‘movie_rating‘]) : ‘‘;
if(empty($movie_rating))
{
$error[] = urldecode(‘Please enter an movie leadactor‘);
}
else if(!is_numeric($movie_rating))
{
$error[] = urlencode(‘Please enter a numeric rating‘);
}
else if($movie_rating < 0 || $movie_rating > 10)
{
$error[] = urlencode(‘Please enter a rating between 1 and 10‘);
}if(empty($error))
{
//var_dump($movie_rating);
//注意是movie_type不是mvioe_type，大错特错
$query = ‘insert into movie(movie_name,movie_year,movie_type,movie_leadactor,movie_director,movie_release,movie_rating)
values("‘.$movie_name.‘",‘.$movie_year.‘,‘.$movie_type.‘,‘.$movie_leadactor.‘,‘.$movie_director.‘,‘.$movie_release.‘,‘.$movie_rating.‘)‘;}
else
{
//注意是Location不是Lacotion，大错特错
header(‘Location:movie_checkformat.php?action=add&error=‘ . join($error , urlencode(‘<br />‘)));
//var_dump($error);
//var_dump($_POST);
}
break;
}
break;
}
case ‘edit‘:
switch($_GET[‘type‘])
{
case ‘movie‘:
{
$error = array();
$movie_name = isset($_POST[‘movie_name‘]) ? trim($_POST[‘movie_name‘]) : ‘‘;
if(empty($movie_name))
{
$error[] = urlencode(‘Please enter an movie name‘);
}$movie_type = isset($_POST[‘movie_type‘]) ? trim($_POST[‘movie_type‘]) : ‘‘;
if(empty($movie_type))
{
$error[] = urldecode(‘Please enter an movie type‘);
}$movie_year = isset($_POST[‘movie_year‘]) ? trim($_POST[‘movie_year‘]) : ‘‘;
if(empty($movie_year))
{
$error[] = urldecode(‘Please enter an movie year‘);
}$movie_leadactor = isset($_POST[‘movie_leadactor‘]) ? trim($_POST[‘movie_leadactor‘]) : ‘‘;
if(empty($movie_leadactor))
{
$error[] = urldecode(‘Please enter an movie leadactor‘);
}$movie_director = isset($_POST[‘movie_director‘]) ? trim($_POST[‘movie_director‘]) : ‘‘;
if(empty($movie_director))
{
$error[] = urldecode(‘Please enter an movie director‘);
}$movie_release = isset($_POST[‘movie_release‘]) ? trim($_POST[‘movie_release‘]) : ‘‘;
if(empty($movie_release))
{
$error[] = urldecode(‘Please enter an movie release‘);
}
else if(!preg_match(‘|^\d{2}-\d{2}-\d{4}$|‘ , $movie_release))
{
$error[] = urlencode(‘Please enter a date in dd-mm-yyyy format‘);
}
else
{
list($day, $month, $year) = explode(‘-‘, $movie_release);
if(!checkdate($month , $day , $year))
{
$error[] = urldecode(‘please enter a validate date‘);
}
else
{
$movie_release = mktime(0, 0, 0, $month, $day, $year);
}
}$movie_rating = isset($_POST[‘movie_rating‘]) ? trim($_POST[‘movie_rating‘]) : ‘‘;
if(empty($movie_rating))
{
$error[] = urldecode(‘Please enter an movie leadactor‘);
}
else if(!is_numeric($movie_rating))
{
$error[] = urlencode(‘Please enter a numeric rating‘);
}
else if($movie_rating < 0 || $movie_rating > 10)
{
$error[] = urlencode(‘Please enter a rating between 1 and 10‘);
}if(empty($error))
{
//var_dump($_POST);
$query = ‘update movie set
movie_name="‘.$_POST[‘movie_name‘].‘",
movie_type=‘.$_POST[‘movie_type‘].‘,
movie_year=‘.$_POST[‘movie_year‘].‘,
movie_leadactor=‘.$_POST[‘movie_leadactor‘].‘,
movie_director=‘.$_POST[‘movie_director‘]. ‘
movie_release=‘.$_POST[‘movie_release‘].‘
movie_rating=‘.$_POST[‘movie_rating‘].‘
where movie_id=‘.$_POST[‘movie_id‘];
}
else
{
//注意是Location不是Lacotion，大错特错
header(‘Location:movie_checkformat.php?action=add&error=‘ . join($error , urlencode(‘<br />‘)));
}
}
break;
}
break;
default:
break;
}
if(isset($query))
{
mysql_query($query,$db) or die(mysql_error($db));
}
?>
<html>
<head>
<title>Commit</title>
</head>
<body>
<p>Done!</p>
</body>
</html>
其实逻辑很简答的，看下面的代码
$movie_leadactor = isset($_POST[‘movie_leadactor‘]) ?
trim($_POST[‘movie_leadactor‘]) :
‘‘;
if(empty($movie_leadactor))
{
$error[] =
urldecode(‘Please enter an movie leadactor‘);
}
其实就是使用isset方法来验证输入是否为空，如果是空的话把错误信息记入到一个数组$error中，然后使用header方法跳转到填写信息的页面中，跳转的方法看上去有点糟糕，如下header(‘Location:movie_checkformat.php?action=add&error=‘
. join($error , urlencode(‘<br
/>‘)));，是将所有错误信息使用换行符来连接起来放到url中来跳转，很我觉得这个有点不合适的。
来看填写信息的页面movie_checkformat.php，
<?php
$db = mysql_connect(‘localhost‘,‘root‘,‘Ctrip07185419‘) or die(‘can not connect to mysql‘);
mysql_select_db(‘moviesite‘,$db) or die(mysql_error($db));
mysql_query(‘set names gbk‘,$db);
if(isset($_GET[‘action‘]) && $_GET[‘action‘] == ‘edit‘)
{
$query = ‘SELECT movie_name,movie_type,movie_year,movie_leadactor,movie_director,movie_release,movie_rating FROM movie WHERE movie_id=‘.$_GET[‘id‘];
//echo $query;
$result = mysql_query($query , $db) or die(mysql_error($db));
extract(mysql_fetch_assoc($result));
}
else
{
$movie_name=‘‘;
$movie_type=0;
$movie_year=date(‘Y‘);
$movie_leadactor=0;
$movie_director=0;
$movie_release=time();
$movie_rating=5;
}
?>
<html>
<head>
<title><?php echo ucfirst($_GET[‘action‘]);?> Movie</title>
<style type="text/css">
<!--
#error { background-color: #600; border: 1px solid #FF0; color: #FFF; text-align: center; margin: 10px; padding: 10px; }
-->
</style>
</head>
<body>
<?php
if(isset($_GET[‘error‘]) && $_GET[‘error‘] != ‘‘)
{
echo ‘<div id="error">‘.$_GET[‘error‘].‘</div>‘;
}
?>
<form action="commit.php?action=<?php echo $_GET[‘action‘];?>&type=movie" method="post">
<table>
<tr>
<td>Movie Name</td>
<td><input type="text" name="movie_name" value="<?php echo $movie_name;?>"/></td>
</tr>
<tr>
<td>Movie Type</td>
<td><select name="movie_type" id="">
<?php
$query = ‘select movietype_id,movietype_label from movietype order by movietype_label‘;
$result = mysql_query($query , $db) or die(mysql_error($db));
while($row = mysql_fetch_assoc($result))
{
if($row[‘movietype_id‘] == $movie_type)
{
echo ‘<option value="‘.$row["movietype_id"].‘" selected="selected">‘.$row["movietype_label"].‘</option>‘;
}
else
{
echo ‘<option value="‘.$row["movietype_id"].‘">‘.$row["movietype_label"].‘</option>‘;
}
}
?>
</select></td>
</tr>
<tr>
<td>Movie Year</td>
<td><select name="movie_year" id="">
<?php
for($yr = date(‘Y‘);$yr>1970;$yr--)
{
if($yr == $movie_year)
{
echo ‘<option value="‘.$yr.‘" selected="selected">‘.$yr.‘</option>‘;
}
else
{
echo ‘<option value="‘.$yr.‘">‘.$yr.‘</option>‘;
}
}
?>
</select></td>
</tr>
<tr>
<td>Lead actor</td>
<td><select name="movie_leadactor" id="">
<?php
$query = ‘select people_id,people_fullname from people where people_isactor = 1 order by people_fullname‘;
$result = mysql_query($query,$db) or die(mysql_error($db));
while($row = mysql_fetch_assoc($result))
{
if($row["people_id"] == $movie_leadactor)
{
echo ‘<option value="‘.$row["people_id"].‘" selected="selected">‘.$row["people_fullname"].‘</option>‘;
}
else
{
echo ‘<option value="‘.$row["people_id"].‘">‘.$row["people_fullname"].‘</option>‘;
}}
?>
</select></td>
</tr>
<tr>
<td>Director</td>
<td><select name="movie_director" id="">
<?php
$query = ‘select * from people where people_isdirector=1 order by people_fullname‘;
$result = mysql_query($query , $db) or die(mysql_error($db));
while($row = mysql_fetch_assoc($result))
{
if($row[‘people_id‘] == $movie_director)
{
echo ‘<option value="‘.$row[‘people_id‘].‘" selected="selected">‘.$row["people_fullname"].‘</option>‘;
}
else
{
echo ‘<option value="‘.$row[‘people_id‘].‘">‘.$row["people_fullname"].‘</option>‘;
}
}
?>
</select></td>
</tr>
<tr>
<td>Movie release date <br /><small>(dd-mm-YYYY)</small></td>
<td>
<input type="text" name="movie_release" value="<?php echo date(‘d-m-y‘ , $movie_release);?>" />
</td>
</tr>
<tr>
<td>Movie rating <br /><small></small></td>
<td><input type="text" name="movie_rating" value="<?php echo $movie_rating;?>"/></td>
</tr>
<tr>
<td colspan="2" style="text-align:center">
<?php
if(‘edit‘ == $_GET[‘action‘])
{
echo ‘<input type="hidden" value="‘.$_GET["id"].‘" name="movie_id"/>‘;
}
?>
<input type="submit" name="submit" value="<?php echo ucfirst($_GET[‘action‘]);?>"/>
</td>
</tr>
</table>
</form>
</body>
</html>
在html中的body开始的时候如果传递的error参数不为空则输出错误信息，代码如下：
<?php
if(isset($_GET[‘error‘]) && $_GET[‘error‘] !=
‘‘)
{
echo ‘<div
id="error">‘.$_GET[‘error‘].‘</div>‘;
}
?>
很简单，这种写法也很糟糕，完全可以放在javascript中来实现，估计实际生产中很少会有人这么写的。
这里顺便看看一些常见的判断方法：
is_array()：判断变量是否是一个数组
is_binary()：
判断变量是否是一个二进制串
is_bool()：判断布尔类型变量true还是false，1还是0
is_callable():
判断变量是否是一个可以访问的函数，估计就是判断是否是代理类型
is_int(): 判断整型
is_null():
判断是否为空
is_numeric():判断是否是数字或者数字形式的字符串吧
is_object():
判断变量是否是一个对象
is_resource(): 判断资源类型
is_string(): 判断是否是字符串类型
is_unicode():
判断是否是unicode字符串
某些时候使用is_xx方法比较慢，使用ctype_xx类型的方法较快，但是它只能检验字符串类型，不能检验对象，数组，资源类型。ctype_xx方法举例如下：
ctype_alnum(): 判断变量是否是数字类型字符串
ctype_alpha(): 判断变量全是字符串
ctype_cntrl():
判断是控制字符，就是转移字符如"\n"
ctype_digit():
判断字符串全部是数字字符，不包含任何非数组字符"."这样的也不包含
ctype_graph(): 检查是否有任何可打印字符，除了空格（补）
ctype_lower()
: 检查小写字母
ctype_print():
检查是否都是可打印字符，就是不包含转移字符，和ctype_control()是相斥的
ctype_punct(): 检查是否有任何可打印字符而不是空格或字母数字字符
ctype_space():
检查是否都是空白字符
ctype_upper() :
检查是否都是大写字符
ctype_xdigit(): 检查是否是16进制的字符串，只能包括 “0123456789abcdef”
还可以使用preg_match来检验输入，这个是用正则表达式的方式来进行检验的。