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diff --git a/files/ar/web/javascript/reference/global_objects/json/index.html b/files/ar/web/javascript/reference/global_objects/json/index.html new file mode 100644 index 0000000000..60305cbd07 --- /dev/null +++ b/files/ar/web/javascript/reference/global_objects/json/index.html @@ -0,0 +1,215 @@ +--- +title: JSON +slug: Web/JavaScript/Reference/Global_Objects/JSON +tags: + - JSON + - JavaScript + - NeedsTranslation + - Object + - Reference + - TopicStub + - polyfill +translation_of: Web/JavaScript/Reference/Global_Objects/JSON +--- +<div>{{JSRef("Global_Objects", "JSON")}}</div> + +<h2 id="Summary" name="Summary">Summary</h2> +<p>The <strong><code>JSON</code></strong> object contains methods for parsing <a class="external" href="http://json.org/">JavaScript Object Notation</a> ({{glossary("JSON")}}) and converting values to JSON. It can't be called or constructed, and aside from its two method properties it has no interesting functionality of its own.</p> + +<h2 id="Description" name="Description">Description</h2> + +<h3 id="JavaScript_Object_Notation" name="JavaScript_Object_Notation">JavaScript Object Notation</h3> +<p>JSON is a syntax for serializing objects, arrays, numbers, strings, booleans, and {{jsxref("null")}}. It is based upon JavaScript syntax but is distinct from it: some JavaScript is not JSON, and some JSON is not JavaScript. See also <a href="http://timelessrepo.com/json-isnt-a-javascript-subset">JSON: The JavaScript subset that isn't</a>.</p> +<table> + <caption>JavaScript and JSON differences</caption> + <thead> + <tr> + <th scope="col">JavaScript type</th> + <th scope="col">JSON differences</th> + </tr> + </thead> + <tbody> + <tr> + <td>Objects and Arrays</td> + <td>Property names must be double-quoted strings; trailing commas are forbidden.</td> + </tr> + <tr> + <td>Numbers</td> + <td>Leading zeros are prohibited; a decimal point must be followed by at least one digit.</td> + </tr> + <tr> + <td>Strings</td> + <td> + <p>Only a limited sets of characters may be escaped; certain control characters are prohibited; the Unicode line separator (<a href="http://unicode-table.com/en/2028/">U+2028</a>) and paragraph separator (<a href="http://unicode-table.com/en/2029/">U+2029</a>) characters are permitted; strings must be double-quoted. See the following example where {{jsxref("JSON.parse()")}} works fine and a {{jsxref("SyntaxError")}} is thrown when evaluating the code as JavaScript:</p> +<pre class="brush: js"> +var code = '"\u2028\u2029"'; +JSON.parse(code); // works fine +eval(code); // fails +</pre> + </td> + </tr> + </tbody> +</table> +<p>The full JSON syntax is as follows:</p> +<pre><var>JSON</var> = <strong>null</strong> + <em>or</em> <strong>true</strong> <em>or</em> <strong>false</strong> + <em>or</em> <var>JSONNumber</var> + <em>or</em> <var>JSONString</var> + <em>or</em> <var>JSONObject</var> + <em>or</em> <var>JSONArray</var> + +<var>JSONNumber</var> = <strong>-</strong> <var>PositiveNumber</var> + <em>or</em> <var>PositiveNumber</var> +<var>PositiveNumber</var> = DecimalNumber + <em>or</em> <var>DecimalNumber</var> <strong>.</strong> <var>Digits</var> + <em>or</em> <var>DecimalNumber</var> <strong>.</strong> <var>Digits</var> <var>ExponentPart</var> + <em>or</em> <var>DecimalNumber</var> <var>ExponentPart</var> +<var>DecimalNumber</var> = <strong>0</strong> + <em>or</em> <var>OneToNine</var> <var>Digits</var> +<var>ExponentPart</var> = <strong>e</strong> <var>Exponent</var> + <em>or</em> <strong>E</strong> <var>Exponent</var> +<var>Exponent</var> = <var>Digits</var> + <em>or</em> <strong>+</strong> <var>Digits</var> + <em>or</em> <strong>-</strong> <var>Digits</var> +<var>Digits</var> = <var>Digit</var> + <em>or</em> <var>Digits</var> <var>Digit</var> +<var>Digit</var> = <strong>0</strong> through <strong>9</strong> +<var>OneToNine</var> = <strong>1</strong> through <strong>9</strong> + +<var>JSONString</var> = <strong>""</strong> + <em>or</em> <strong>"</strong> <var>StringCharacters</var> <strong>"</strong> +<var>StringCharacters</var> = <var>StringCharacter</var> + <em>or</em> <var>StringCharacters</var> <var>StringCharacter</var> +<var>StringCharacter</var> = any character + <em>except</em> <strong>"</strong> <em>or</em> <strong>\</strong> <em>or</em> U+0000 through U+001F + <em>or</em> <var>EscapeSequence</var> +<var>EscapeSequence</var> = <strong>\"</strong> <em>or</em> <strong>\/</strong> <em>or</em> <strong>\\</strong> <em>or</em> <strong>\b</strong> <em>or</em> <strong>\f</strong> <em>or</em> <strong>\n</strong> <em>or</em> <strong>\r</strong> <em>or</em> <strong>\t</strong> + <em>or</em> <strong>\u</strong> <var>HexDigit</var> <var>HexDigit</var> <var>HexDigit</var> <var>HexDigit</var> +<var>HexDigit</var> = <strong>0</strong> through <strong>9</strong> + <em>or</em> <strong>A</strong> through <strong>F</strong> + <em>or</em> <strong>a</strong> through <strong>f</strong> + +<var>JSONObject</var> = <strong>{</strong> <strong>}</strong> + <em>or</em> <strong>{</strong> <var>Members</var> <strong>}</strong> +<var>Members</var> = <var>JSONString</var> <strong>:</strong> <var>JSON</var> + <em>or</em> <var>Members</var> <strong>,</strong> <var>JSONString</var> <strong>:</strong> <var>JSON</var> + +<var>JSONArray</var> = <strong>[</strong> <strong>]</strong> + <em>or</em> <strong>[</strong> <var>ArrayElements</var> <strong>]</strong> +<var>ArrayElements</var> = <var>JSON</var> + <em>or</em> <var>ArrayElements</var> <strong>,</strong> <var>JSON</var> +</pre> +<p>Insignificant whitespace may be present anywhere except within a <code><var>JSONNumber</var></code> (numbers must contain no whitespace) or <code><var>JSONString</var></code> (where it is interpreted as the corresponding character in the string, or would cause an error). The tab character (<a href="http://unicode-table.com/en/0009/">U+0009</a>), carriage return (<a href="http://unicode-table.com/en/000D/">U+000D</a>), line feed (<a href="http://unicode-table.com/en/000A/">U+000A</a>), and space (<a href="http://unicode-table.com/en/0020/">U+0020</a>) characters are the only valid whitespace characters.</p> + +<h2 id="Methods" name="Methods">Methods</h2> +<dl> + <dt>{{jsxref("JSON.parse()")}}</dt> + <dd>Parse a string as JSON, optionally transform the produced value and its properties, and return the value.</dd> + <dt>{{jsxref("JSON.stringify()")}}</dt> + <dd>Return a JSON string corresponding to the specified value, optionally including only certain properties or replacing property values in a user-defined manner.</dd> +</dl> + +<h2 id="Polyfill" name="Polyfill">Polyfill</h2> +<p>The <code>JSON</code> object is not supported in older browsers. You can work around this by inserting the following code at the beginning of your scripts, allowing use of <code>JSON</code> object in implementations which do not natively support it (like Internet Explorer 6).</p> +<p>The following algorithm is an imitation of the native <code>JSON</code> object:</p> +<pre class="brush: js">if (!window.JSON) { + window.JSON = { + parse: function(sJSON) { return eval('(' + sJSON + ')'); }, + stringify: function(vContent) { + if (vContent instanceof Object) { + var sOutput = ''; + if (vContent.constructor === Array) { + for (var nId = 0; nId < vContent.length; sOutput += this.stringify(vContent[nId]) + ',', nId++); + return '[' + sOutput.substr(0, sOutput.length - 1) + ']'; + } + if (vContent.toString !== Object.prototype.toString) { + return '"' + vContent.toString().replace(/"/g, '\\$&') + '"'; + } + for (var sProp in vContent) { + sOutput += '"' + sProp.replace(/"/g, '\\$&') + '":' + this.stringify(vContent[sProp]) + ','; + } + return '{' + sOutput.substr(0, sOutput.length - 1) + '}'; + } + return typeof vContent === 'string' ? '"' + vContent.replace(/"/g, '\\$&') + '"' : String(vContent); + } + }; +} +</pre> +<p>More complex well-known <a class="external" href="http://remysharp.com/2010/10/08/what-is-a-polyfill/">polyfills</a> for the <code>JSON</code> object are <a class="link-https" href="https://github.com/douglascrockford/JSON-js">JSON2</a> and <a class="external" href="http://bestiejs.github.com/json3">JSON3</a>.</p> + +<h2 id="Specifications" name="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('ES5.1', '#sec-15.12', 'JSON')}}</td> + <td>{{Spec2('ES5.1')}}</td> + <td> </td> + </tr> + <tr> + <td>{{SpecName('ES6', '#sec-json-object', 'JSON')}}</td> + <td>{{Spec2('ES6')}}</td> + <td> </td> + </tr> + </tbody> +</table> + +<h2 id="Browser_compatibility" name="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>{{CompatVersionUnknown}}</td> + <td>{{CompatGeckoDesktop("1.9.1")}}</td> + <td>{{CompatIE("8.0")}}</td> + <td>{{CompatOpera("10.5")}}</td> + <td>{{CompatSafari("4.0")}}</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>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatGeckoMobile("1.0")}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + </tr> + </tbody> + </table> +</div> +<p>Based on <a class="external" href="http://kangax.github.com/es5-compat-table/">Kangax's compat table</a>.</p> + +<h2 id="See_also" name="See_also">See also</h2> +<ul> + <li><a href="/en-US/docs/Web/JavaScript/Guide/Using_native_JSON">Using native <code>JSON</code></a></li> + <li>{{jsxref("Date.prototype.toJSON()")}}</li> +</ul> |