I have a text.
$text='userpics/115/X3WGOC0009JA.jpg';
I want to add a letter p before X3WGOC0009JA.jpg, so my output will be
$text='userpics/115/pX3WGOC0009JA.jpg';
---^
I am new to php, so I don't really know what to try, I was hoping you could guide me in the right direction
You can explode by the slash by one way.
$exploded_text = explode('/', $text);
$new_text = $exploded_text[0] . $exploded_text[1] . 'p' . $exploded_text[2];
It's not the best way, but it will work.
Based on his question, I think all he wants to do is:
$text='userpics/115/'.'p'.'X3WGOC0009JA.jpg';
First, I would get the filename using strrpos and substr:
$text = 'userpics/115/X3WGOC0009JA.jpg';
$prepend_filename = 'p';
$last_slash_pos = strrpos($text, '/');
if ($last_slash_pos === false) throw new Exception('No slashes found');
$path = substr($text, 0, $last_slash_pos);
$filename = substr($text, $last_slash_pos + 1); // Add one to skip slash
And then you can add the p (as specified in $prepend_filename) using this:
$new_path = $path . DIRECTORY_SEPARATOR . $prepend_filename . $filename;
Have you tried just setting you variables and concatenation if you doing this a bunch.
$p = 'p';
$new = "userpics/115/" . $p . "X3WGOC0009JA.jpg";
There is a function, substr_replace(), which can insert a string at a point you want.
We combine this with strRpos() which we can use to find the first slash, LOOKING IN REVERSE:
$string = substr_replace($string, 'p', strrpos($string, '/')+1 );
This will insert 'p' in $string. At the position of the '/' in $string. The +1 corrects the 'cursor' to the character AFTER the slash.
Why not use the explode functions?
Very simple: Those are slow. String functions like strpos() and substr_replace() are VERY fast, especially on small strings.
Arrays are WAY slower in php, so don't go there unless you have to. For simple string- manipulation you should use simple string functions (sounds easy when you put it like that doesnt it?).
In a simple test I benchmarked the explode variant like user3758531's VS the string variant like mine:
100.000 tries with arrays: 1.5 sec
100.000 tries with strings: 0.9 sec
In this one situation, with this one action timing doesnt really matter. But apply this way of thinking thoughout the website and you will notice it speeding up/slowing down.
Related
I have a path "../uploads/e2c_name_icon/" and I need to extract e2c_name_icon from the path.
What I tried is using str_replace function
$msg = str_replace("../uploads/","","../uploads/e2c_name_icon/");
This result in an output "e2c_name_icon/"
$msg=str_replace("/","","e2c_name_icon/")
There is a better way to do this. I am searching alternative method to use regex expression.
Try this. Outputs: e2c_name_icon
<?php
$path = "../uploads/e2c_name_icon/";
// Outputs: 'e2c_name_icon'
echo explode('/', $path)[2];
However, this is technically the third component of the path, the ../ being the first. If you always need to get the third index, then this should work. Otherwise, you'll need to resolve the relative path first.
Use basename function provided by PHP.
$var = "../uploads/e2c_name_icon/";
echo basename( $var ); // prints e2c_name_icon
If you are strictly want to get the last part of the url after '../uploads'
Then you could use this :
$url = '../uploads/e2c_name_icon/';
$regex = '/\.\.\/uploads\/(\w+)/';
preg_match($regex, $url, $m)
print_r ($m); // $m[1] would output your url if possible
You can trim after the str_replace.
echo $msg = trim(str_replace("../uploads/","","../uploads/e2c_name_icon/"), "/");
I don't think you need to use regex for this. Simple string functions are usually faster
You could also use strrpos to find the second last /, then trim off both /.
$path = "../uploads/e2c_name_icon/";
echo $msg = trim(substr($path, strrpos($path, "/",-2)),"/");
I added -2 in strrpos to skip the last /. That means it returns the positon of the / after uploads.
So substr will return /e2c_name_icon/ and trim will remove both /.
You'd be much better off using the native PHP path functions vs trying to parse it yourself.
For example:
$path = "../uploads/e2c_name_icon/";
$msg = basename(dirname(realpath($path))); // e2c_name_icon
Given the following URL:
http://www.domain.com/reporting/category-breakdown.php?re=updated
I need to remove everything after the .php
It might be "?re=updated" or it could be something else. The number of characters won't always be the same, the string will always end with .php though.
How do I do this?
To find the first position of a substring in a string you can use strpos() in PHP.
$mystring = 'http://www.domain.com/reporting/category-breakdown.php?re=updated';
$findme = '.php';
$pos = strpos($mystring, $findme);
After, you have the position of the first character of your substring '.php' in your URL. You want to get the URL until the end of '.php', that means the position you get + 4 (substring length). To get this, you can use substr(string,start,length) function.
substr($mystring, 0, $pos + 4);
Here you are!
Find the first indexOf (".php"), then use substring from char 0 to your index + the length of (".php");
3 line solution:
$str = "http://www.domain.com/reporting/category-breakdown.php?re=updated";
$str = array_shift(explode('?', $str));
echo $str;
Note: it's not fool-proof and could fail in several cases, but for the kind of URLs you mentioned, this works.
Here is another way to get the non-query-string part of a url with PHP:
$url = 'http://www.domain.com/reporting/category-breakdown.php?re=updated';
$parsed = parse_url($url);
$no_query_string = $parsed['scheme'] . '://' . $parsed['hostname'] . $parsed['path'];
// scheme: http, hostname: www.domain.com, path: /reporting/category-breakdown.php
That will handle .php, .phtml, .htm, .html, .aspx, etc etc.
Link to Manual page.
I know it may sound as a common question but I have difficulty understanding this process.
So I have this string:
http://domain.com/campaign/tgadv?redirect
And I need to get only the word "tgadv". But I don't know that the word is "tgadv", it could be whatever.
Also the url itself may change and become:
http://domain.com/campaign/tgadv
or
http://domain.com/campaign/tgadv/
So what I need is to create a function that will get whatever word is after campaign and before any other particular character. That's the logic..
The only certain thing is that the word will come after the word campaign/ and that any other character that will be after the word we are searching is a special one ( i.e. / or ? )
I tried understanding preg_match but really cannot get any good result from it..
Any help would be highly appreciated!
I would not use a regex for that. I would use parse_url and basename:
$bits = parse_url('http://domain.com/campaign/tgadv?redirect');
$filename = basename($bits['path']);
echo $filename;
However, if want a regex solution, use something like this:
$pattern = '~(.*)/(.*)(\?.*)~';
preg_match($pattern, 'http://domain.com/campaign/tgadv?redirect', $matches);
$filename = $matches[2];
echo $filename;
Actually, preg_match sounds like the perfect solution to this problem. I assume you are having problems with the regex?
Try something like this:
<?php
$url = "http://domain.com/campaign/tgadv/";
$pattern = "#campaign/([^/\?]+)#";
preg_match($pattern, $url, $matches);
// $matches[1] will contain tgadv.
$path = "http://domain.com/campaign/tgadv?redirect";
$url_parts = parse_url($path);
$tgadv = strrchr($url_parts['path'], '/');
You don't really need a regex to accomplish this. You can do it using stripos() and substr().
For example:
$str = '....Your string...';
$offset = stripos($str, 'campaign/');
if ( $offset === false ){
//error, end of h4 tag wasn't found
}
$offset += strlen('campaign/');
$newStr = substr($str, $offset);
At this point $newStr will have all the text after 'campaign/'.
You then just need to use a similar process to find the special character position and use substr() to strip the string you want out.
You can also just use the good old string functions in this case, no need to involve regexps.
First find the string /campaign/, then take the substring with everything after it (tgadv/asd/whatever/?redirect), then find the next / or ? after the start of the string, and everything in between will be what you need (tgadv).
Let's say I have a string like so:
$file = 'widget-widget-newsletter.php';
I want to use preg_replace() to remove the prefix widget- and to remove the suffix .php . Is it possible to use one regular expression to achieve all this?
The resulting string should be widget-newsletter.
$file = preg_replace('/^widget-|\.php$/', '', $file);
Why not use substr? Much simpler and faster.
Don't think of it as stripping off the ends, rather as extracting the middle:
$file = 'widget-widget-newsletter.php';
if (preg_match('/^widget\-(.+)\.php$/i', $file, $matches))
echo "filename is " . $matches[1][0];
Of course, if "widget-" and ".php" are entirely static and are always going to be there, you could just use substr:
echo "filename is " . substr($file, 7, -4);
That would be much faster but if you pass it garbage, you'll get garbage back.
$name = preg_replace(array('%^widget-%', '%-%', '%\.php$%'), array('','_',''), $file);
should do it.
Or more general (assuming the prefix goes to the first - and the suffix starts at the last .):
$name = preg_replacearray('%^.*?-%', '%-%', '%\.(?!.*?\.).*?$%'), array('','_',''), $file);
If you provide an array of patterns and an array of replacements to the function, then each pattern gets replaced by the according replacement.
Update:
As you removed the requirement to replace the - by _, substr() is indeed better suited:
$name = substr($file, 7, -4);
From the manual description of the replacement parameter:
The string or an array with strings to replace. If this parameter is a string and the pattern parameter is an array, all patterns will be replaced by that string.
Sounds like you could use an array with the prefix and suffix patterns in it for the pattern parameter, and just put empty string as the replacement.
I have fooled around with regex but can't seem to get it to work. I have a file called includes/header.php I am converting the file into one big string so that I can pull out a certain portion of the code to paste in the html of my document.
$str = file_get_contents('includes/header.php');
From here I am trying to get return only the string that starts with <ul class="home"> and ends with </ul>
try as I may to figure out an expression I am still confused.
Once I trim down the string I can just print that on my page but I can't figure out the trimming part
If you need something really hardcore, http://www.php.net/manual/en/book.xmlreader.php.
If you just want to rip out the text that fits that pattern try something like this.
$string = "stuff<ul class=\"home\">alsdkjflaskdvlsakmdf<another></another></ul>stuff";
if( preg_match( '/<ul class="home">(.*)<\/ul>/', $string, $match ) ) {
//do stuff with $match[0]
}
I'm assuming that the difficulty you're having has to do with escaping the regex special characters in the string(s) you're using as a delimiter. If so, try using the preg_quote() function:
$start = preg_quote('<ul class="home">');
$end = preg_quote('</ul>', '/');
preg_match("/" . $start. '.*' . $end . "/", $str, $matching_html_snippets);
The html you want should be in $matching_html_snippets[0]
You probably want an XML parser such as the built in one. Here is an example you might want to take a look at.
http://www.php.net/manual/en/function.xml-parse.php#90733
If you want to use regex then something along the lines of
$str = file_get_contents('includes/header.php');
$matchedstr = preg_match("<place your pattern here>", $str, $matches);
You probably want the pattern
'/<ul class="home">.*?<\/ul>/s'
Where $matches will contain an array of the matches it found so you can grab whatever element you want from the array with
$matchedstr[0];
which will return the first element. And then output that.
But I'd be a bit wary, regular expressions do tend to match to surprising edge cases and you need to feed them actual data to get reliable results as to when they are failing. However if you are just passing templates it should be ok, just do some tests and see if it all works. If not I'd still recommend using the PHP XML Parser.
Hope that helps.
If you feel like not using regexes you could use string finding, which I think the PHP manual implies is quicker:
function substrstr($orig, $startText, $endText) {
//get first occurrence of the start string
$start = strpos($orig, $startText);
//get last occurrence of the end string
$end = strrpos($orig, $endText);
if($start === FALSE || $end === FALSE)
return $orig;
$start++;
$length = $end - $start;
return substr($orig, $start, $length);
}
$substr = substrstr($string, '<ul class="home">', '</ul>');
You'll need to make some adjustments if you want to include the terminating strings in the output, but that should get you started!
Here's a novel way to do it; I make no guarantees about this technique's robustness or performance, other than it does work for the example given:
$prefix = '<ul class="home">';
$suffix = '</ul>';
$result = $prefix . array_shift(explode($suffix, array_pop(explode($prefix, $str)))) . $suffix;