1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
---
title: String.fromCodePoint()
slug: Web/JavaScript/Referencia/Objetos_globales/String/fromCodePoint
translation_of: Web/JavaScript/Reference/Global_Objects/String/fromCodePoint
---
<div>{{JSRef("Global_Objects", "String")}}</div>
<h2 id="Summary" name="Summary">Resumen</h2>
<p>El método estatico <strong><code>String.fromCodePoint()</code></strong> devuelve una cadena creada por una secuencia de puntos de codigo.</p>
<h2 id="Syntax" name="Syntax">Sintaxis</h2>
<pre class="syntaxbox"><code>String.fromCodePoint(<var>num1</var>[, ...[, <var>numN</var>]])</code></pre>
<h3 id="Parameters" name="Parameters">Parametros</h3>
<dl>
<dt><code>num1, ..., num<em>N</em></code></dt>
<dd>Una secuencia de puntos de código.</dd>
</dl>
<h3 id="Throws">Throws</h3>
<dl>
<dt>{{jsxref("Global_Objects/RangeError", "RangeError")}}</dt>
<dd>A {{jsxref("Global_Objects/RangeError", "RangeError")}} is thrown if an invalid Unicode code point is given (e.g. "RangeError: NaN is not a valid code point").</dd>
</dl>
<h2 id="Description" name="Description">Descripción</h2>
<p>Because <code>fromCodePoint()</code> is a static method of {{jsxref("Global_Objects/String", "String")}}, you always use it as <code>String.fromCodePoint()</code>, rather than as a method of a {{jsxref("Global_Objects/String", "String")}} object you created.</p>
<h2 id="Examples" name="Examples">Ejemplos</h2>
<h3 id="Example:_Using_fromCharCode" name="Example:_Using_fromCharCode">Ejemplos: Usando <code>fromCodePoint()</code></h3>
<pre class="brush: js">String.fromCodePoint(42); // "*"
String.fromCodePoint(65, 90); // "AZ"
String.fromCodePoint(0x404); // "\u0404"
String.fromCodePoint(0x2F804); // "\uD87E\uDC04"
String.fromCodePoint(194564); // "\uD87E\uDC04"
String.fromCodePoint(0x1D306, 0x61, 0x1D307) // "\uD834\uDF06a\uD834\uDF07"
String.fromCodePoint('_'); // RangeError
String.fromCodePoint(Infinity); // RangeError
String.fromCodePoint(-1); // RangeError
String.fromCodePoint(3.14); // RangeError
String.fromCodePoint(3e-2); // RangeError
String.fromCodePoint(NaN); // RangeError
</pre>
<pre class="brush: js">// String.fromCharCode() alone cannot get the character at such a high code point
// The following, on the other hand, can return a 4-byte character as well as the
// usual 2-byte ones (i.e., it can return a single character which actually has
// a string length of 2 instead of 1!)
console.log(String.fromCodePoint(0x2F804)); // or 194564 in decimal
</pre>
<h2 id="Polyfill" name="Polyfill">Polyfill</h2>
<p>The <code>String.fromCodePoint</code> method has been added to the ECMAScript standard in version 6 and may not be supported in all web browsers or environments yet. Use the code below for a polyfill:</p>
<pre class="brush: js">/*! http://mths.be/fromcodepoint v0.1.0 by @mathias */
if (!String.fromCodePoint) {
(function() {
var defineProperty = (function() {
// IE 8 only supports `Object.defineProperty` on DOM elements
try {
var object = {};
var $defineProperty = Object.defineProperty;
var result = $defineProperty(object, object, object) && $defineProperty;
} catch(error) {}
return result;
}());
var stringFromCharCode = String.fromCharCode;
var floor = Math.floor;
var fromCodePoint = function() {
var MAX_SIZE = 0x4000;
var codeUnits = [];
var highSurrogate;
var lowSurrogate;
var index = -1;
var length = arguments.length;
if (!length) {
return '';
}
var result = '';
while (++index < length) {
var codePoint = Number(arguments[index]);
if (
!isFinite(codePoint) || // `NaN`, `+Infinity`, or `-Infinity`
codePoint < 0 || // not a valid Unicode code point
codePoint > 0x10FFFF || // not a valid Unicode code point
floor(codePoint) != codePoint // not an integer
) {
throw RangeError('Invalid code point: ' + codePoint);
}
if (codePoint <= 0xFFFF) { // BMP code point
codeUnits.push(codePoint);
} else { // Astral code point; split in surrogate halves
// http://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
codePoint -= 0x10000;
highSurrogate = (codePoint >> 10) + 0xD800;
lowSurrogate = (codePoint % 0x400) + 0xDC00;
codeUnits.push(highSurrogate, lowSurrogate);
}
if (index + 1 == length || codeUnits.length > MAX_SIZE) {
result += stringFromCharCode.apply(null, codeUnits);
codeUnits.length = 0;
}
}
return result;
};
if (defineProperty) {
defineProperty(String, 'fromCodePoint', {
'value': fromCodePoint,
'configurable': true,
'writable': true
});
} else {
String.fromCodePoint = fromCodePoint;
}
}());
}
</pre>
<h2 id="Specifications">Specifications</h2>
<table class="standard-table">
<tbody>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
<tr>
<td>{{SpecName('ES6', '#sec-string.fromcodepoint', 'String.fromCodePoint')}}</td>
<td>{{Spec2('ES6')}}</td>
<td>Initial definition.</td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</h2>
<div>{{CompatibilityTable}}</div>
<div id="compat-desktop">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>Chrome</th>
<th>Firefox (Gecko)</th>
<th>Internet Explorer</th>
<th>Opera</th>
<th>Safari</th>
</tr>
<tr>
<td>Basic support</td>
<td>41</td>
<td>{{CompatGeckoDesktop("29")}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
</tr>
</tbody>
</table>
</div>
<div id="compat-mobile">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>Android</th>
<th>Chrome for Android</th>
<th>Firefox Mobile (Gecko)</th>
<th>IE Mobile</th>
<th>Opera Mobile</th>
<th>Safari Mobile</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatGeckoMobile("29")}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
<td>{{CompatNo}}</td>
</tr>
</tbody>
</table>
</div>
<h2 id="See_also" name="See_also">See also</h2>
<ul>
<li>{{jsxref("String.fromCharCode()")}}</li>
<li>{{jsxref("String.prototype.charAt()")}}</li>
<li>{{jsxref("String.prototype.codePointAt()")}}</li>
<li>{{jsxref("String.prototype.charCodeAt()")}}</li>
</ul>
|
