This question already has answers here:
Explode string into array with no empty elements?
(12 answers)
Closed 2 years ago.
I want explode to return an empty array if the delimiter is not found.
Currently, I do something like this to get the explode behavior I want:
if (strpos($line, ' ') === false) {
$entries = [];
} else {
$entries = explode(' ', $line);
}
There must be a more concise way of getting this behavior without having to use preg_split. preg_split has its own behavior that is also undesirable, such as including the delimiter in the resultant array entries.
So, you have a string of space delimited data, e.g. 'foo bar'? Your rule is if there's no delimiter, meaning if the string is either a single value ('foo') or an empty string (''), then you want an empty array; otherwise you want the split delimited data?
$entries = explode(' ', $line);
if (count($entries) < 2) {
$entries = [];
}
There isn't really a sane way to make this specific condition shorter, but this removes the redundant inspection of the string and clearly states what the code is trying to do.
Related
This question already has answers here:
My regex is matching too much. How do I make it stop? [duplicate]
(5 answers)
Closed 2 years ago.
I have to modify an URL like this:
$string = "/st:1/sc:RsrlYQhSQvs=/fp:1/g:3/start:2015-07-01/end:2015-07-30";
Namely, I want to delete st:1 with a regex. I used:
preg_replace("/\/st:(.*)\//",'',$string)
but I got
end:2015-07-30
while I would like to get:
/sc:RsrlYQhSQvs=/fp:1/g:3/start:2015-07-01/end:2015-07-30
Same if I would like to delete fp:1.
You can use:
$string = preg_replace('~/st:[^/]*~','',$string);
[^/]* will only match till next /
You are using greedy matching with . that matches any character.
Use a more restricted pattern:
preg_replace("/\/st:[^\/]*/",'',$string)
The [^\/]* negated character class only matches 0 or more characters other than /.
Another solution would be to use lazy matching with *? quantifier, but it is not that efficient as with the negated character class.
FULL REGEX EXPLANATION:
\/st: - literal /st:
[^\/]* - 0 or more characters other than /.
You need to add ? in your regex:-
<?php
$string = "/st:1/sc:RsrlYQhSQvs=/fp:1/g:3/start:2015-07-01/end:2015-07-30";
echo preg_replace("/\/st:(.*?)\//",'',$string)
?>
Output:- https://eval.in/397658
Based on this same you can do for next things also.
Instead of using regex here you should make parsing utility functions for your special format string, they are simple, they don't take to long to write and they will make your life a lot easier:
function readPath($path) {
$parameters = array();
foreach(explode('/', $path) as $piece) {
// Here we make sure we have something
if ($piece == "") {
continue;
}
// This here is just a fancy way of splitting the array returned
// into two variables.
list($key, $value) = explode(':', $piece);
$parameters[$key] = $value;
}
return $parameters;
}
function writePath($parameters) {
$path = "";
foreach($parameters as $key => $value) {
$path .= "/" . implode(":", array($key, $value));
}
return $path;
}
Now you can just work on it as a php array, in this case you would go:
$parameters = readPath($string);
unset($parameters['st']);
$string = writePath($parameters);
This makes for much more readable and reusable code, additionally since most of the time you are dealing with only slight variations of this format you can just change the delimiters each time or even abstract these functions to using different delimiters.
Another way to deal with this is to convert the string to conform to a normal path query, using something like:
function readPath($path) {
return parse_str(strtr($path, "/:", "&="));
}
In your case though since you are using the "=" character in a url you would also need to url encode each value so as to not conflict with the format, this would involve similarly structured code to above though.
This question already has answers here:
Search in array with relevance
(5 answers)
Closed 9 years ago.
I am trying to search an array for a list of words(areas).
But sometime the word(area) in the array is 2 words.
i.e in the array is "Milton Keynes" so "Milton" is not being matched
Is there any way i can do this, without splitting any double words in the array (as i assume this will be a big load on the server)
Below is an example of what i am doing
foreach (preg_split("/(\s)|(\/)|(\W)/", $words) as $word){
if (in_array($word, $areaArray)){
$AreaID[] = array_search($word, $areaArray);
}
}
Grateful, as always for any advice!
You could use preg_grep():
$re = sprintf('/\b%s\b/', preg_quote($search, '/'));
// ...
if (preg_grep($re, $areaArray)) {
// we have a match
}
You can opt to make the match case insensitive by adding the /i modifier.
You can use regular expression to find a value, this will work similar to MySQL like function
$search='Milton Keynes';
foreach ($areaArray as $key => $value) {
if (preg_match('~'.preg_quote($search).'~i',$value)) {
echo "$key";
}
}
This question already has answers here:
Fastest way of deleting a value in a comma separated list
(4 answers)
Closed 2 years ago.
I am storing numbers in a database with a string like 5,55,15,17,2,35
I want to remove say number 5 from the string, keeping the comma seperation set like it is.
The problem with using str_replace() is that all of the 5's will be removed. If i use str_replace('5,'', $string) thats fine, but the comma wouldn't be after the 5 if it was in the middle of the string or at the end. That same str_replace would also remove part of 15, and 55,
Am i missing something?
$array = explode(',', $string);
foreach ($array as $k => $v)
if ($v == 5) unset($array[$k]);
$string = implode(',', $array);
You probably shouldn't be storing a comma separated list of values in a single database column in the first place. It looks like a one-to-many association, which should be modeled with a separate table.
Split the string first by comma so you can work with the numbers directly. Remove 5 from the array, then recombine the array into a comma-delimited string.
Here's an example:
<?php
$input = '5,55,15,17,2,35';
echo "Input: $input<br />";
// Split the string by "exploding" the string on the delimiter character
$nums = explode(',', $input);
// Remove items by comparing to an array containing unwanted elements
$nums = array_diff($nums, array(5));
// Combine the array back into a comma-delimited string
$output = implode(',', $nums);
echo "Output: $output<br />";
// Outputs:
// Input: 5,55,15,17,2,35
// Output: 55,15,17,2,35
?>
str_replace([$num.",",",".$num],"",$input);
U can try something like this:
// Convert string into array of numbers
$arrOfNumbers = explode(',', $string);
// Find id of number for del
$numberForDelId = array_search($numberForDel, $arrOfNumbers);
//Delete number
unset($arrOfNumbers[$numberForDelId]);
// Convert back to string
$resultString = implode(',' $arrOfNumbers)
You should:
get the string
then "explode" the values into an array
and re-create the string without the number you want to remove.
I have a string like abcdefg123hijklm. I also have an array which contains several strings like [456, 123, 789].
I want to check if the number in the middle of abcdefg123hijklm exists in the array.
How can I do that? I guess in_array() won't work.
So you want to check if any substring of that particular string (lets call it $searchstring) is in the array?
If so you will need to iterate over the array and check for the substring:
foreach($array as $string)
{
if(strpos($searchstring, $string) !== false)
{
echo 'yes its in here';
break;
}
}
See: http://php.net/manual/en/function.strpos.php
If you want to check if a particular part of the String is in the array you will need to use substr() to separate that part of the string and then use in_array() to find it.
http://php.net/manual/en/function.substr.php
Another option would be to use regular expressions and implode, like so:
if (preg_match('/'.implode('|', $array).'/', $searchstring, $matches))
echo("Yes, the string '{$matches[0]}' was found in the search string.");
else
echo("None of the strings in the array were found in the search string.");
It's a bit less code, and I would expect it to be more efficient for large search strings or arrays, since the search string will only have to be parsed once, rather than once for every element of the array. (Although you do add the overhead of the implode.)
The one downside is that it doesn't return the array index of the matching string, so the loop might be a better option if you need that. However, you could also find it with the code above followed by
$match_index = array_search($matches[0], $array);
Edit: Note that this assumes you know your strings aren't going to contain regular expression special characters. For purely alphanumeric strings like your examples that will be true, but if you're going to have more complex strings you would have to escape them first. In that case the other solution using a loop would probably be simpler.
You can do it reversely. Assume your string is $string and array is $array.
foreach ($array as $value)
{
// strpos can return 0 as a first matched position, 0 == false but !== false
if (strpos($string, $value) !== false)
{
echo 'Matched value is ' . $value;
}
}
Use this to get your numbers
$re = "/(\d+)/";
$str = "abcdefg123hijklm";
preg_match($re, $str, $matches);
and ( 123 can be $matches[1] from above ):
preg_grep('/123/', $array);
http://www.php.net/manual/en/function.preg-grep.php
This question already has answers here:
Php compare strings and return common values
(3 answers)
Closed 8 years ago.
I have two strings of keywords
$keystring1 = "tech,php,radio,love";
$keystring2 = "Mtn,huntung,php,tv,tech";
How do i do return keywords that common in both strings
You can do this:
$common = array_intersect(explode(",", $keystring1), explode(",", $keystring2));
If you want them back into strings, you can just implode it back.
Hmm, interesting question... You can use this.
$arr1 = explode(',',$keystring1);
$arr2 = explode(',',$keystring2);
$duplicates = array_intersect($arr1,$arr2);
foreach($duplicates as $word) {
echo $word;
}
You could explode() both strings on commas into arrays and loop through the first array checking to see if any of the words exist in the second array using the in_array() function. If so then add that word to a "common words" array.
Those are going to need to be arrays not variables.
$keystring1 = array('tech','php','radio','love');
$keystring2 = array('mtn','huntung','php','tv','tech');
First of all...