I am running some simple code from http://www.writephponline.com/
Inputs
$str = "$Q$14";
$arr = explode("$", $str);
print_r($arr);
Outputs
Array ( [0] => [1] => 14 )
My question is why array at index 0 is empty, shouldn't that be letter Q?
Please check the photo
The main problem is the choice of the double quoted string type:
$Q = '$Q';
print_r(explode('$', "$Q$14"));
Array ( [0] => [1] => Q [2] => 14 )
So what is happening in your code is a "double quoted" string replaces valid variable names to the value of them, where $Q is a valid name and $14 is not because they may not start with a digit.
echo "$Q$14";
Notice: Undefined variable: Q in ... on line ...
$14
So you're actually concatenating null . '$14' as variable $Q does not exist in your code and that value is null so the end value is: $14
If you would use a 'literal' string, it works as expected:
echo '$Q$14';
$Q$14
The other thing is that explode() splits the string into 2 pieces from the first delimiter found, so you will have a left and a right part. Any traditional delimiter found only causes 1 index to be appended. The string starts with a delimiter so the first array index is expected to be null because no value exists left of the first character.
print_r(explode('.', 'left.right'));
print_r(explode('.', 'left.middle.right'));
print_r(explode('$', '$Q$14'));
Array ( [0] => left [1] => right )
Array ( [0] => left [1] => middle [2] => right )
Array ( [0] => [1] => Q [2] => 14 )
If you really want to achieve desired output with the same string you specified then try this one, add backslash(\) before first $
$str = "\$Q$14";
$arr = explode("$", $str);
print_r($arr);
I tried it and it worked.
Related
I need a help to parse the characters inside those brackets:
[]
{}
<>
{|}
<|>
For example, I have this string variable (Japanese):
$question = "この<部屋|へや>[に]{椅子|いす}[が]ありません";
Expected result in HTML:
Description
1) This is a particle. I will convert all word inside [] into HTML tag. Example: [に] will be converted into <span style="color:blue">に</span>. A full sentence can have multiple []. Note: I understand how to use str_replace.
2 and 4) This is normal kanji word which will be used as a question to the user. A full sentence can only have one {}.
3 and 5) This is normal kanji text. A full sentence can have multiple {}.
2, 3, 4, and 5) They will converted into Ruby html tags. Sometimes they will not have a | separator, which is not mandatory. From what I understand, I just need to explode the | characters. If explode return false or | not exist, I will use original value. Note: I understand how to use ruby tags (rb and rt).
My question
How do I parse characters 1-5 I mentioned above with PHP? What keyword I need to start?
Thanks.
Thanks to this page: Capturing text between square brackets in PHP, now I have my own answer.
Full code:
<?php
$text = "この<部屋|へや>[に]{椅子|いす}[が]ありません";
preg_match_all("/\[([^\]]*)\]/", $text, $square_brackets); //[]
preg_match_all("/{([^}]*)}/", $text, $curly_brackets); //{}
preg_match_all("/<([^}]*)>/", $text, $angle_brackets); //<>
print_r($square_brackets);
echo "\r\n";
print_r($curly_brackets);
echo "\r\n";
print_r($angle_brackets);
echo "\r\n";
Result:
Array
(
[0] => Array
(
[0] => [に]
[1] => [が]
)
[1] => Array
(
[0] => に
[1] => が
)
)
Array
(
[0] => Array
(
[0] => {椅子|いす}
)
[1] => Array
(
[0] => 椅子|いす
)
)
Array
(
[0] => Array
(
[0] => <部屋|へや>
)
[1] => Array
(
[0] => 部屋|へや
)
)
Thanks.
Im trying to split string in PHP. I should split string using two delimiters: new line and comma. My code is:
$array = preg_split("/\n|,/", $str)
But i get string split using comma, but not using \n. Why is that? Also , do I have to take into account "\r\n" symbol?
I can think of two possible reasons that this is happening.
1. You are using a single quoted string:
$array = preg_split("/\n|,/", 'foo,bar\nbaz');
print_r($array);
Array
(
[0] => foo
[1] => bar\nbaz
)
If so, use double quotes " instead ...
$array = preg_split("/\n|,/", "foo,bar\nbaz");
print_r($array);
Array
(
[0] => foo
[1] => bar
[2] => baz
)
2. You have multiple newline sequences and I would recommend using \R if so. This matches any Unicode newline sequence that is in the ASCII range.
$array = preg_split('/\R|,/', "foo,bar\nbaz\r\nquz");
print_r($array);
Array
(
[0] => foo
[1] => bar
[2] => baz
[3] => quz
)
I use a regex to get a value from a document and store it in a variable called $distance. That is a string, but I have to put it in an int column of a table in a database.
Of course, normally I would go and say
$distance=intval($distance);
But it doesn't work! I really don't know why.
This is all I am doing:
preg_match_all($regex,$content,$match);
$distance=$match[0][1];
$distance=intval($distance);
The regex is correct, if I echo $distance, it is e.g. "0" - but I need it to be 0 instead of "0". Using intval() will somehow always convert it to an empty string.
EDIT 1
The regex is this:
$regex='#<value>(.+?)</value>#'; // Please, I know I shouldn't use regex for parsing XML - but that is not the problem right now
Then I proceed with
preg_match_all($regex,$content,$match);
$distance=$match[0][1];
$distance=intval($distance);
If you'd do print_r($match) you'd see that the array you need is $match[1]:
$content = '<value>1</value>, <value>12</value>';
$regex='#<value>(.+?)</value>#';
preg_match_all($regex,$content,$match);
print_r($match);
Output:
Array
(
[0] => Array
(
[0] => <value>1</value>
[1] => <value>12</value>
)
[1] => Array
(
[0] => 1
[1] => 12
)
)
In this case:
$distance = (int) $match[1][1];
var_dump($distance);
Output: int(12)
Alternatively, you can use PREG_SET_ORDER flag, i.e. preg_match_all($regex,$content,$match,$flags=PREG_SET_ORDER);, $match array has this structure:
Array
(
[0] => Array
(
[0] => <value>1</value>
[1] => 1
)
[1] => Array
(
[0] => <value>12</value>
[1] => 12
)
)
There must be a space, or possibly (been there, done that) an 0xA0 byte before the zero. Use "\d" in your regexp to be sure to get digits.
Edit: you can clean up the value with
$value = (int)trim($value, " \t\r\n\x0B\xA0\x00");
http://php.net/manual/en/function.trim.php
Why do you need the question mark in your regex? Try this:
$regex='#<value>(.+)</value>#';
I have a string like that :
0d(Hi)i(Hello)4d(who)i(where)540d(begin)i(began)
And i want to make it an array with that.
I try first to add separator, in order to use the php function explode.
;0,d(Hi),i(Hello);4,d(who),i(where);540,d(begin),i(began)
It works but the problem is I want to minimize the separator to save disk space.
Therefore i want to know by using preg_split, regular expression, if it's possible to have a huge array like that without using separator :
Array ( [0] => Array ( [0] => 0 [1] => d(hi) [2] => i(Hello) )
[1] => Array ( [0] => 4 [1] => d(who) [2] => i(where) )
[2] => Array ( [0] => 540 [1] => d(begin) [2] => i(began) )
)
I try some code & regex, but I saw that the value in the regular expression was not present in the final result (like explode function, in the final array we do not have the delimitor.)
More over, i have some difficulties to build the regex. Here is the one that I made :
$modif = preg_split("/[0-9]+(d(.+))?(i(.+))?/", $data);
I must precise that d() and i() can not be present (but at least one)
Thanks
If you do
preg_match_all('/(\d+)(d\([^()]*\))?(i\([^()]*\))?/', $subject, $result, PREG_SET_ORDER);
on your original string, then you'll get an array where
$result[$i][0]
contains the ith match (i. e. $result[0][0] would be 0d(Hi)i(Hello)) and where
$result[$i][$c]
contains the cth capturing group of the ith match (i. e. $result[0][1] is 0, $result[0][2] is d(Hi) and $result[0][2] is i(Hello)).
Is that what you wanted?
Lets say I have a string "My name is $name and my pet is $animal"
How to check if string has variables inside it? And if has, add to array like
$array = ("$name","animal");
Would it be some pregmatch? but then all $+sometextafterthesymbol needs to be extracted and $ with space after it left alone.
Any ideas?
You can use regular expressions for this. The following will match any dollar sign followed by 1 or more word characters (letters, numbers, or underscore):
preg_match_all('/\$(\w+)/', $string, $matches);
$matches:
Array
(
[0] => Array
(
[0] => $name
[1] => $animal
)
[1] => Array
(
[0] => name
[1] => animal
)
)
Remember that $string, if hardcoded, must be wrapped in single quotes (').