phpjs
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JavaScript
function substr(str, start, len) {
// Returns part of a string
//
// version: 909.322
// discuss at: http://phpjs.org/functions/substr
// + original by: Martijn Wieringa
// + bugfixed by: T.Wild
// + tweaked by: Onno Marsman
// + revised by: Theriault
// + improved by: Brett Zamir (http://brett-zamir.me)
// % note 1: Handles rare Unicode characters if 'unicode.semantics' ini (PHP6) is set to 'on'
// * example 1: substr('abcdef', 0, -1);
// * returns 1: 'abcde'
// * example 2: substr(2, 0, -6);
// * returns 2: false
// * example 3: ini_set('unicode.semantics', 'on');
// * example 3: substr('a\uD801\uDC00', 0, -1);
// * returns 3: 'a'
// * example 4: ini_set('unicode.semantics', 'on');
// * example 4: substr('a\uD801\uDC00', 0, 2);
// * returns 4: 'a\uD801\uDC00'
// * example 5: ini_set('unicode.semantics', 'on');
// * example 5: substr('a\uD801\uDC00', -1, 1);
// * returns 5: '\uD801\uDC00'
// * example 6: ini_set('unicode.semantics', 'on');
// * example 6: substr('a\uD801\uDC00z\uD801\uDC00', -3, 2);
// * returns 6: '\uD801\uDC00z'
// * example 7: ini_set('unicode.semantics', 'on');
// * example 7: substr('a\uD801\uDC00z\uD801\uDC00', -3, -1)
// * returns 7: '\uD801\uDC00z'
// Add: (?) Use unicode.runtime_encoding (e.g., with string wrapped in "binary" or "Binary" class) to
// allow access of binary (see file_get_contents()) by: charCodeAt(x) & 0xFF (see https://developer.mozilla.org/En/Using_XMLHttpRequest ) or require conversion first?
var i = 0,
allBMP = true,
es = 0,
el = 0,
se = 0,
ret = '';
str += '';
var end = str.length;
// BEGIN REDUNDANT
this.php_js = this.php_js || {};
this.php_js.ini = this.php_js.ini || {};
// END REDUNDANT
switch ((this.php_js.ini['unicode.semantics'] && this.php_js.ini['unicode.semantics'].local_value.toLowerCase())) {
case 'on':
// Full-blown Unicode including non-Basic-Multilingual-Plane characters
// strlen()
for (i = 0; i < str.length; i++) {
if (/[\uD800-\uDBFF]/.test(str.charAt(i)) && /[\uDC00-\uDFFF]/.test(str.charAt(i + 1))) {
allBMP = false;
break;
}
}
if (!allBMP) {
if (start < 0) {
for (i = end - 1, es = (start += end); i >= es; i--) {
if (/[\uDC00-\uDFFF]/.test(str.charAt(i)) && /[\uD800-\uDBFF]/.test(str.charAt(i - 1))) {
start--;
es--;
}
}
} else {
var surrogatePairs = /[\uD800-\uDBFF][\uDC00-\uDFFF]/g;
while ((surrogatePairs.exec(str)) != null) {
var li = surrogatePairs.lastIndex;
if (li - 2 < start) {
start++;
} else {
break;
}
}
}
if (start >= end || start < 0) {
return false;
}
if (len < 0) {
for (i = end - 1, el = (end += len); i >= el; i--) {
if (/[\uDC00-\uDFFF]/.test(str.charAt(i)) && /[\uD800-\uDBFF]/.test(str.charAt(i - 1))) {
end--;
el--;
}
}
if (start > end) {
return false;
}
return str.slice(start, end);
} else {
se = start + len;
for (i = start; i < se; i++) {
ret += str.charAt(i);
if (/[\uD800-\uDBFF]/.test(str.charAt(i)) && /[\uDC00-\uDFFF]/.test(str.charAt(i + 1))) {
se++; // Go one further, since one of the "characters" is part of a surrogate pair
}
}
return ret;
}
break;
}
// Fall-through
case 'off':
// assumes there are no non-BMP characters;
// if there may be such characters, then it is best to turn it on (critical in true XHTML/XML)
default:
if (start < 0) {
start += end;
}
end = typeof len === 'undefined' ? end : (len < 0 ? len + end : len + start);
// PHP returns false if start does not fall within the string.
// PHP returns false if the calculated end comes before the calculated start.
// PHP returns an empty string if start and end are the same.
// Otherwise, PHP returns the portion of the string from start to end.
return start >= str.length || start < 0 || start > end ? !1 : str.slice(start, end);
}
return undefined; // Please Netbeans
}