» Javascript equivalent for PHP's array_diff

PHP to Javascript Project: php.js

php.jsThis article is part of the 'Porting PHP to Javascript' Project, which aims to decrease the gap between developing for PHP & Javascript.

A lot of people are familiar with PHP's functions, and though Javascript functions are often quite similar, some functions may be missing or addressed differently. The Javascript implementations should be as compliant with the PHP versions as possible, a good indication is that the PHP function manual could also apply to the Javascript version.

Porting crucial PHP functions to Javascript can be fun & useful. Currently some PHP functions have been added, but readers are encouraged to contribute and improve functions by adding comments. Eventually the goal is to save all the functions in one php.js file and make it publicly available for your coding pleasure.

If you choose to contribute, let me know how you want to be credited in the function's comments. You may also want to subscribe to RSS so you receive updates whenever new functions are posted.

This is a Javascript version of the PHP function: array_diff.

PHP array_diff

Description

array_diff - Computes the difference of arrays

array array_diff( array array1 , array array2 [, array...] )

Compares array1 against array2 and returns the difference.

See Also

Javascript array_diff

Source

This is the main source of the Javascript version of PHP's array_diff

function array_diff (array) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: Sanjoy Roy
    // *     example 1: array_diff(['Kevin', 'van', 'Zonneveld'], ['van', 'Zonneveld']);
    // *     returns 1: ['Kevin']
 
    var arr_dif = [], i = 1, argc = arguments.length, argv = arguments, key, key_c, found=false, cntr=0;
 
    // loop through 1st array
    for ( key in array ){
        // loop over other arrays
        for (i = 1; i< argc; i++){
            // find in the compare array
            found = false;
            for (key_c in argv[i]) {
                if (argv[i][key_c] == array[key]) {
                    found = true;
                    break;
                }
            }
 
            if(!found){
                //arr_dif[key] = array[key];
                arr_dif[cntr] = array[key];
                cntr++;
            }
        }
    }
 
    return arr_dif;
}

Examples

Currently there is 1 example

Example 1

This is how you could call array_diff()
array_diff(['Kevin', 'van', 'Zonneveld'], ['van', 'Zonneveld']);
And that would return
['Kevin']

More about this Project

Download php.js

To easily include it in your code, every function currently available is stored in

Normal

Namespaced What is 'namespaced?'

To download use Right click, Save Link As
Generally the best way is to use a minified version and gzip it



Testing the functions

The number of functions is growing fast and so it becomes hard to maintain quality.

To defeat that danger of bad code, syntax errors, etc, I've added a new feature: php.js tester.

It is an automatically generated page that includes ALL functions in your browser, and then extracts specific testing information from each function's comments. This info is then used to run the function, and the return value is compared to a predefined one.

This way code is always checked on syntax errors, and if it doesn't function correctly anymore after an update, we should also be able to detect it more easily.

If you want, go check it out.


Credits

Respect & awards go to everybody who has contributed in some way so far:

medalmedalMichael White (link) for contributing to:
 array_count_values, get_included_files, include, include_once, require, require_once, md5, number_format, parse_str, printf, sha1, sprintf, str_pad, strnatcmp, http_build_query, floatval, is_object, print_r
spacemedal_argos for contributing to:
 array_fill, array_pad, array_product, array_rand, compact, count, range, abs, defined, ip2long, long2ip, implode, strcmp, ucwords
spacemedalJonas Raoni Soares Silva (link) for contributing to:
 shuffle, abs, setcookie, number_format, number_format, soundex, str_repeat, str_replace, str_rot13, ucwords, wordwrap, wordwrap
spacemedalLegaev Andrey for contributing to:
 end, reset, file, file_get_contents, function_exists, include, include_once, http_build_query, is_array, is_object
spacemedalAtes Goral (link) for contributing to:
 array_change_key_case, array_count_values, array_diff_key, get_class, preg_quote, addslashes, count_chars, str_rot13, stripslashes
spacemedalPhilip Peterson for contributing to:
 sizeof, round, echo, nl2br, str_replace, strchr, urldecode, urlencode, var_export
spacemedalMartijn Wieringa for contributing to:
 str_ireplace, str_split, strcasecmp, stripos, strnatcmp, substr
spacemedalWebtoolkit.info (link) for contributing to:
 crc32, md5, sha1, utf8_decode, utf8_encode
 
spacemedalCarlos R. L. Rodrigues (link) for contributing to:
 array_chunk, array_unique, date, levenshtein
spacemedalAsh Searle (link) for contributing to:
 basename, printf, sprintf
spacemedalErkekjetter for contributing to:
 ltrim, rtrim, trim
spacemedalmarrtins for contributing to:
 array_change_key_case, addslashes, stripslashes
spacemedalAlfonso Jimenez (link) for contributing to:
 array_reduce, strpbrk
spacemedalAman Gupta for contributing to:
 base64_decode, utf8_decode
spacemedalArpad Ray (mailto:arpad@php.net) for contributing to:
 serialize, unserialize
spacemedalKarol Kowalski for contributing to:
 array_reverse, abs
spacemedalThunder.m for contributing to:
 base64_decode, base64_encode
spacemedalTyler Akins (link) for contributing to:
 base64_decode, base64_encode
spacemedalmdsjack (link) for contributing to:
 include, trim
spacemedalAlexander Ermolaev (link) for contributing to:
 trim
spacemedalAllan Jensen (link) for contributing to:
 number_format
spacemedalAndrea Giammarchi (link) for contributing to:
 array_map
spacemedalBayron Guevara for contributing to:
 base64_encode
spacemedalBenjamin Lupton for contributing to:
 number_format
spacemedalBrad Touesnard for contributing to:
 date
spacemedalBrett Zamir for contributing to:
 str_split
spacemedalCagri Ekin for contributing to:
 parse_str
spacemedalCord for contributing to:
 is_array
spacemedalDavid for contributing to:
 is_numeric
spacemedalDavid James for contributing to:
 get_class
spacemedalDxGx for contributing to:
 trim
spacemedalFGFEmperor for contributing to:
 mktime
spacemedalFelix Geisendoerfer (link) for contributing to:
 array_key_exists
spacemedalFremyCompany for contributing to:
 isset
spacemedalGabriel Paderni for contributing to:
 str_replace
spacemedalLeslie Hoare for contributing to:
 rand
spacemedalLincoln Ramsay for contributing to:
 basename
spacemedalMeEtc (link) for contributing to:
 date
spacemedalMick@el for contributing to:
 stripslashes
spacemedalNick Callen for contributing to:
 wordwrap
spacemedalOzh for contributing to:
 dirname
spacemedalPedro Tainha (link) for contributing to:
 unserialize
spacemedalPeter-Paul Koch (link) for contributing to:
 date
spacemedalPhilippe Baumann for contributing to:
 empty
spacemedalSakimori for contributing to:
 strlen
spacemedalSanjoy Roy for contributing to:
 array_diff
spacemedalSimon Willison (link) for contributing to:
 str_replace
spacemedalSteve Clay for contributing to:
 function_exists
spacemedalSteve Hilder for contributing to:
 strcmp
spacemedalSteven Levithan (link) for contributing to:
 trim
spacemedalT0bsn for contributing to:
 crc32
spacemedalThiago Mata (link) for contributing to:
 call_user_func_array
spacemedalTim Wiel for contributing to:
 date
spacemedalXoraX (link) for contributing to:
 dirname
spacemedalbaris ozdil for contributing to:
 mktime
spacemedalbooeyOH for contributing to:
 preg_quote
spacemedaldjmix for contributing to:
 basename
spacemedalduncan for contributing to:
 array_unique
spacemedalecho is bad for contributing to:
 echo
spacemedalgabriel paderni for contributing to:
 mktime
spacemedalger for contributing to:
 html_entity_decode
spacemedaljohn (link) for contributing to:
 html_entity_decode
spacemedalkenneth for contributing to:
 explode
spacemedalpenutbutterjelly for contributing to:
 str_ireplace
spacemedalstensi for contributing to:
 intval

Your name here?

Contributing is as easy as adding a comment with better code, or code for a new function.
Any contribution leading to improvement will directly get your name & link here.


Coming Project features

Project features that we are currently working on:

  • Versioning. Individual functions are versioned, but the entire library should be versioned as well.
  • Light. A lightweight version of php.js should be made available with only common functions in it.

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tags: programming, php, javascript
category: Programming - Javascript - PHP equivalents
read: 857 times

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Comments

#4. Kevin on 13 March 2008

Kevin@ Sanjoy Roy: Thank you, added!

#3. Re-Ordering the Index on 13 March 2008

Re-Ordering the Index/////////////////////////////////////////////////////////// /* Sanjoy Roy's comments: ------------------------------- I have added a counter variable (cntr) and return array returns ordered array. This will help to get rid of 'undefined' values in the list when we use them in our program. */ //////////////////////////////////////////////////////////

function array_diff (array) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // *     example 1: array_diff(['Kevin', 'van', 'Zonneveld'], ['van', 'Zonneveld']);
    // *     returns 1: ['Kevin']
 
    var arr_dif = [], i = 1, argc = arguments.length, argv = arguments, key, key_c, found=false, cntr=0;
 
    // loop through 1st array
    for ( key in array ){
        // loop over other arrays
        for (i = 1; i< argc; i++){
            // find in the compare array
            found = false;
            for (key_c in argv[i]) {
                if (argv[i][key_c] == array[key]) {
                    found = true;
                    break;
                }
            }
 
            if(!found){
                //arr_dif[key] = array[key];
                arr_dif[cntr] = array[key];
                cntr++;
            }
        }
    }
 
    return arr_dif;
};

#2. Kevin on 22 January 2008

Kevin@ Ates Goral: All together superb contributions. Greatly formatted and very consistent. I also like that you've included the example-return pairs in the comments. Thanks a LOT!

#1. Ates Goral on 22 January 2008

Ates GoralHere's array_diff_key():

function array_diff_key(object) {
    // *     example 1: array_diff_key({red: 1, green: 2, blue: 3, white: 4});
    // *     returns 1: {"red":1, "green":2, "blue":3, "white":4}
    // *     example 2: array_diff_key({red: 1, green: 2, blue: 3, white: 4}, {red: 5});
    // *     returns 2: {"green":2, "blue":3, "white":4}
    // *     example 3: array_diff_key({red: 1, green: 2, blue: 3, white: 4}, {red: 5}, {green: 6, blue: 7});
    // *     returns 3: {"white":4}
    // *     example 4: array_diff_key({red: 1, green: 2, blue: 3, white: 4}, {red: 5}, {red: 5});
    // *     returns 4: {"green":2, "blue":3, "white":4}
    
    var ret = new Object();
    
    for (var key in object) {
        ret[key] = object[key];
    }
    
    for (var argidx = 1; argidx < arguments.length; ++argidx) {
        var other = arguments[argidx];
        
        if (other instanceof Object) {
            for (var key in other) {
                delete ret[key];    
            }
        }
    }
    
    return ret;
}