PHP preg_match meaning and issue

问题

Currently I have this code:

<?php
if (isset($_GET['id'])) {
$itemid = $_GET['id'];
$search = "$itemid";
$query = ucwords($search);
$string = file_get_contents('http://clubpenguincheatsnow.com/tools/newitemdatabase/items.php');
if($itemid=="")
{
echo "Please fill out the form.";
}
else
{
$string = explode('<br>',$string);
foreach($string as $row)
{
preg_match('/^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/', trim($row), $matches);
if(strstr($matches[1], $query))
{
echo "<a href='http://clubpenguincheatsnow.com/tools/newitemdatabase/info.php?id=$matches[2]'>";
echo $matches[1];
echo "</a><br>";
}
}
if($matches[1]=="")
{
echo "Item does not exist!";
}
}
}
else {
echo "Item does not exist!";
}
?>

What I want to know is what does this section mean? preg_match('/^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/', trim($row), $matches); mainly the /^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/ part is what I am wondering about.

Also, an issue that I have been having is how can I allow it to use numbers too? Because I have another file that has the data (http://clubpenguincheatsnow.com/tools/newitemdatabase/items.php) and it want it to grab everything, even the names with the numbers.

How do I do this though? Please help me! Any help would be VERY HIGHLY appreciated!

回答1:

That is a regular expression.

The '^' matches the beginning of a string.

The '\D' matches any character that is not a digit.

The '\d' matches any digit.

The '\s' matches any whitespace.

The plus sign means that the previous character can occur multiple times.

So basically it would match all those lines in your file, except that last comma.

Blue = 1 = No = 20

That line would match the regex.

About your last question to allow numbers too, use this:

/^(.+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/

回答2:

the code is a regular expression:

/^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/

the code will use the regular expression to cut the string um pieces and put in an array ($matches)

preg_match('/^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/', trim($row), $matches);

You shall use the code to see better

print_r($matches)

To find by name or by item number change the code

if(strstr($matches[1], $query))

if(isset($matches[1]) && (strstr($matches[1], $query) || $matches[2] == $query) )

Your code shall look like this...

if (isset($_GET['id'])) {
$itemid = $_GET['id'];
$search = "$itemid";
$query = ucwords($search);
$string = file_get_contents('http://clubpenguincheatsnow.com/tools/newitemdatabase/items.php');
if($itemid=="")
{
echo "Please fill out the form.";
}
else
{
$string = explode('<br>',$string);
foreach($string as $row)
{
preg_match('/^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/', trim($row), $matches);
if(isset($matches[1]) && (strstr($matches[1], $query) || $matches[2] == $query) )

{
echo "<a href='http://clubpenguincheatsnow.com/tools/newitemdatabase/info.php?id=$matches[2]'>";
echo $matches[1];
echo "</a><br>";
}
}
}
}
else {
echo "Item does not exist!";
}

回答3:

/^(\D+)\s=\s(\d+)\s=\s(\D+)\s=\s(\d+)/

This regular expression will match any number of non-numeric character, followed by a whitespace character, followed by equals, and so on. For example, this

asd = 1 = yh = 23

To allow numbers in the names:

/^(\w+)\s=\s(\d+)\s=\s(\w+)\s=\s(\d+)/

To allow numbers and alpha-numeric chars in everything:

/^(\w+)\s=\s(\w+)\s=\s(\w+)\s=\s(\w+)/

To include spaces and ' too:

/^([\w\s']+)\s=\s([\w\s']+)\s=\s([\w\s']+)\s=\s([\w\s']+)/

回答4:

The code, as said by Sena, is a regular expression. It is capturing four groups with "=" in between them.

group 1: (\D+) : any character that is not a digit one or more times
group 2: (\d+) : any character that is a digit one or more times
group 3: (\D+) : same as one
group 4: (\d+) : same as two.

So, it will match something like this: a = 1 = bc = 2

So, it is matching numbers, what do you want it to do? try print_r($matches) as suggested above.

来源：https://stackoverflow.com/questions/10963473/php-preg-match-meaning-and-issue

标签

php

scripting

preg-match