From de5c456ebded0e038adbf23db34cc290c8829180 Mon Sep 17 00:00:00 2001 From: Florian Merz Date: Thu, 11 Feb 2021 14:49:24 +0100 Subject: unslug pl: move --- .../global_objects/string/fromcodepoint/index.html | 149 +++++++++++++++++++++ 1 file changed, 149 insertions(+) create mode 100644 files/pl/web/javascript/reference/global_objects/string/fromcodepoint/index.html (limited to 'files/pl/web/javascript/reference/global_objects/string/fromcodepoint') diff --git a/files/pl/web/javascript/reference/global_objects/string/fromcodepoint/index.html b/files/pl/web/javascript/reference/global_objects/string/fromcodepoint/index.html new file mode 100644 index 0000000000..a8c17af7f1 --- /dev/null +++ b/files/pl/web/javascript/reference/global_objects/string/fromcodepoint/index.html @@ -0,0 +1,149 @@ +--- +title: String.fromCodePoint() +slug: Web/JavaScript/Referencje/Obiekty/String/fromCodePoint +translation_of: Web/JavaScript/Reference/Global_Objects/String/fromCodePoint +--- +
{{JSRef}}
+ +

The static String.fromCodePoint() method returns a string created by using the specified sequence of code points.

+ +
{{EmbedInteractiveExample("pages/js/string-fromcodepoint.html","shorter")}}
+ + + +

Syntax

+ +
String.fromCodePoint(num1[, ...[, numN]])
+ +

Parameters

+ +
+
num1, ..., numN
+
A sequence of code points.
+
+ +

Return value

+ +

A string created by using the specified sequence of code points.

+ +

Exceptions

+ + + +

Description

+ +

This method returns a string (and not a {{jsxref("String")}} object).

+ +

Because fromCodePoint() is a static method of {{jsxref("String")}}, you must call it as String.fromCodePoint(), rather than as a method of a {{jsxref("String")}} object you created.

+ +

Polyfill

+ +

The String.fromCodePoint() method has been added to ECMAScript 2015 and may not be supported in all web browsers or environments yet.

+ +

Use the code below for a polyfill:

+ +
if (!String.fromCodePoint) (function(stringFromCharCode) {
+    var fromCodePoint = function(_) {
+      var codeUnits = [], codeLen = 0, result = "";
+      for (var index=0, len = arguments.length; index !== len; ++index) {
+        var codePoint = +arguments[index];
+        // correctly handles all cases including `NaN`, `-Infinity`, `+Infinity`
+        // The surrounding `!(...)` is required to correctly handle `NaN` cases
+        // The (codePoint>>>0) === codePoint clause handles decimals and negatives
+        if (!(codePoint < 0x10FFFF && (codePoint>>>0) === codePoint))
+          throw RangeError("Invalid code point: " + codePoint);
+        if (codePoint <= 0xFFFF) { // BMP code point
+          codeLen = codeUnits.push(codePoint);
+        } else { // Astral code point; split in surrogate halves
+          // https://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
+          codePoint -= 0x10000;
+          codeLen = codeUnits.push(
+            (codePoint >> 10) + 0xD800,  // highSurrogate
+            (codePoint % 0x400) + 0xDC00 // lowSurrogate
+          );
+        }
+        if (codeLen >= 0x3fff) {
+          result += stringFromCharCode.apply(null, codeUnits);
+          codeUnits.length = 0;
+        }
+      }
+      return result + stringFromCharCode.apply(null, codeUnits);
+    };
+    try { // IE 8 only supports `Object.defineProperty` on DOM elements
+      Object.defineProperty(String, "fromCodePoint", {
+        "value": fromCodePoint, "configurable": true, "writable": true
+      });
+    } catch(e) {
+      String.fromCodePoint = fromCodePoint;
+    }
+}(String.fromCharCode));
+
+ +

Examples

+ +

Using fromCodePoint()

+ +

Valid input:

+ +
String.fromCodePoint(42);       // "*"
+String.fromCodePoint(65, 90);   // "AZ"
+String.fromCodePoint(0x404);    // "\u0404" == "Є"
+String.fromCodePoint(0x2F804);  // "\uD87E\uDC04"
+String.fromCodePoint(194564);   // "\uD87E\uDC04"
+String.fromCodePoint(0x1D306, 0x61, 0x1D307); // "\uD834\uDF06a\uD834\uDF07"
+
+ +

Invalid input:

+ +
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
+
+ +

Compared to fromCharCode()

+ +

{{jsxref("String.fromCharCode()")}} cannot return supplementary characters (i.e. code points 0x010000 – 0x10FFFF) by specifying their code point. Instead, it requires the UTF-16 surrogate pair in order to return a supplementary character:

+ +
String.fromCharCode(0xD83C, 0xDF03); // Code Point U+1F303 "Night with
+String.fromCharCode(55356, 57091);   // Stars" == "\uD83C\uDF03"
+
+ +

String.fromCodePoint(), on the other hand, can return 4-byte supplementary characters, as well as the more common 2-byte BMP characters, by specifying their code point (which is equivalent to the UTF-32 code unit):

+ +
String.fromCodePoint(0x1F303); // or 127747 in decimal
+
+ +

Specifications

+ + + + + + + + + + + + +
Specification
{{SpecName('ESDraft', '#sec-string.fromcodepoint', 'String.fromCodePoint')}}
+ +

Browser compatibility

+ + + +

{{Compat("javascript.builtins.String.fromCodePoint")}}

+ +

See also

+ + -- cgit v1.2.3-54-g00ecf