» Javascript equivalent for PHP's substr
146 PHP equivalents
- PHP.JS Licensing
- PHP.JS SVN
- PHP.JS Namespaced
- abs
- addslashes
- array
- array_change_key_case
- array_chunk
- array_combine
- array_count_values
- array_diff
- array_diff_assoc
- array_diff_key
- array_fill
- array_flip
- array_keys
- array_key_exists
- array_map
- array_pad
- array_pop
- array_product
- array_push
- array_rand
- array_reduce
- array_reverse
- array_search
- array_shift
- array_sum
- array_unique
- array_unshift
- array_values
- array_walk
- array_walk_recursive
- base64_decode
- base64_encode
- basename
- bin2hex
- call_user_func_array
- checkdate
- chr
- compact
- count
- count_chars
- crc32
- create_function
- date
- defined
- dirname
- echo
- empty
- end
- explode
- file
- file_get_contents
- floatval
- function_exists
- get_class
- get_included_files
- htmlentities
- htmlspecialchars
- htmlspecialchars_decode
- html_entity_decode
- http_build_query
- implode
- include
- include_once
- intval
- in_array
- ip2long
- isset
- is_array
- is_int
- is_null
- is_numeric
- is_object
- is_string
- join
- krsort
- ksort
- levenshtein
- long2ip
- ltrim
- md5
- md5_file
- mktime
- nl2br
- number_format
- ord
- parse_str
- preg_quote
- printf
- print_r
- rand
- range
- require
- require_once
- reset
- round
- rsort
- rtrim
- serialize
- setcookie
- sha1
- sha1_file
- shuffle
- sizeof
- sort
- soundex
- split
- sprintf
- strcasecmp
- strchr
- strcmp
- stripos
- stripslashes
- strip_tags
- stristr
- strlen
- strnatcmp
- strpbrk
- strpos
- strrev
- strripos
- strrpos
- strstr
- strtolower
- strtoupper
- str_ireplace
- str_pad
- str_repeat
- str_replace
- str_rot13
- str_split
- » substr
- substr_count
- time
- trim
- ucfirst
- ucwords
- unserialize
- urldecode
- urlencode
- utf8_decode
- utf8_encode
- var_export
- wordwrap
PHP to Javascript Project: php.js
This 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: substr.
PHP substr
Description
substr - Return part of a string
string substr( string string , int start [, int length] )
Returns the portion of string specified by the start and length parameters.
Parameters
-
string
The input string.
-
start
If start is non-negative, the returned string will start at the start 'th position in string , counting from zero. For instance, in the string 'abcdef', the character at position 0 is 'a', the character at position 2 is 'c', and so forth.
If start is negative, the returned string will start at the start 'th character from the end of string .
Example#1 Using a negative start
<?php
$rest = substr("abcdef", -1); // returns "f"
$rest = substr("abcdef", -2); // returns "ef"
$rest = substr("abcdef", -3, 1); // returns "d"
?> -
length
If length is given and is positive, the string returned will contain at most length characters beginning from start (depending on the length of string ). If string is less than or equal to start characters long, FALSE will be returned.
If length is given and is negative, then that many characters will be omitted from the end of string (after the start position has been calculated when a start is negative). If start denotes a position beyond this truncation, an empty string will be returned.
Example#2 Using a negative length
<?php
$rest = substr("abcdef", 0, -1); // returns "abcde"
$rest = substr("abcdef", 2, -1); // returns "cde"
$rest = substr("abcdef", 4, -4); // returns ""
$rest = substr("abcdef", -3, -1); // returns "de"
?>
Return Values
Returns the extracted part of string.
See Also
Javascript substr
Source
This is the main source of the Javascript version of PHP's substr
function substr( f_string, f_start, f_length ) { // http://kevin.vanzonneveld.net // + original by: Martijn Wieringa // * example 1: substr('abcdef', 0, -1); // * returns 1: 'abcde' if(f_start < 0) { f_start += f_string.length; } if(f_length == undefined) { f_length = f_string.length; } else if(f_length < 0){ f_length += f_string.length; } else { f_length += f_start; } if(f_length < f_start) { f_length = f_start; } return f_string.substring(f_start, f_length); }
Examples
Currently there is 1 example
Example 1
substr('abcdef', 0, -1);And that would return
'abcde'More about this Project
Download php.js
To easily include it in your code, every function currently available is stored in
Normal
- uncompressed source: php.js (169.4kB)
- minified: php.min.js (62.1kB) [recommended]
- compressed: php.packed.js (45.4kB)
Namespaced What is 'namespaced?'
- uncompressed source: php.namespaced.js (208.7kB)
- minified: php.namespaced.min.js (62.3kB)
- compressed: php.namespaced.packed.js (45.6kB)
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.
If you want, go check it out.
Credits
Respect & awards go to everybody who has contributed in some way so far:
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.
- Site. A place for PHP.JS of it's own. You can track our lame attempts at phpjs.org (not hyperlinked deliberately). If there are any CakePHP developers out there who would like to contribute, contact me.
- Testsuite. A better test-suite that can be ran locally so developers can easily test before commiting. Also the testing itself should be more thorough.
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category: Programming - Javascript - PHP equivalents
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