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<h1 style="text-align: center;">language object - "the global object"</h1>
<h2>[WHAT]</h2>
<ol>
<li><strong>]&nbsp;you don't create&nbsp;"the global object", it is created automatically,</strong></li>
<ol>
<li>] for each new window in your web site/application</li>
</ol>
<li><strong>] it contains</strong></li>
<ol>
<li>] the properties and&nbsp;methods(functions) listed below</li>
<li>] AND any&nbsp;'globally scoped'&nbsp;objects that "your code" contains&nbsp;</li>
</ol>
<li><strong>]&nbsp;"the global object"&nbsp;is&nbsp;"global" in "scope"</strong></li>
<ol>
<li>] so you can access it's(properties/methods) from anywhere in your</li>
</ol>
<li><strong>] do not confuse this with the ...</strong></li>
<ol>
<li>] the "Object object" -</li>
<li>] "global scope"&nbsp;- which refers to 'any object variables' that you can access from anywhere in your code.</li>
</ol></ol>
<h2>[WHY]</h2>
<ol>
<li><strong>[properties]</strong></li>
<ol>
<li>] undefined -</li>
<li>] Infinity -</li>
<li>] Nan -</li>
<li>] Null -</li>
</ol>
<li><strong>[methods] </strong></li>
<ol>
<li>] <a title="The eval() method evaluates JavaScript code represented as a string." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval" target="_blank"><code>eval()</code></a></li>
<li>] <a title="The uneval() method creates an string representation of the source code of an Object." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/uneval" target="_blank"><code>uneval()</code></a></li>
<li>] <a title="The global isFinite() function determines whether the passed value is a finite number. If needed, the parameter is first converted to a number." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/isFinite" target="_blank"><code>isFinite()</code></a></li>
<li>] <a title="The isNaN() function determines whether a value is NaN or not. Note: coercion inside the isNaN function has interesting rules; you may alternatively want to use Number.isNaN(), as defined in ECMAScript 6, or you can use typeof to determine if the value is Not-A-Number." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN" target="_blank"><code>isNaN()</code></a></li>
<li>] <a title="The parseFloat() function parses a string argument and returns a floating point number." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseFloat" target="_blank"><code>parseFloat()</code></a></li>
<li>] <a title="The parseInt() function parses a string argument and returns an integer of the specified radix (the base in mathematical numeral systems)." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt" target="_blank"><code>parseInt()</code></a></li>
<li>] <a title="The decodeURI() function decodes a Uniform Resource Identifier (URI) previously created by encodeURI or by a similar routine." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURI" target="_blank"><code>decodeURI()</code></a></li>
<li>] <a title="The decodeURIComponent() method decodes a Uniform Resource Identifier (URI) component previously created by encodeURIComponent or by a similar routine." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURIComponent" target="_blank"><code>decodeURIComponent()</code></a></li>
<li>] <a title="The encodeURI() method encodes a Uniform Resource Identifier (URI) by replacing each instance of certain characters by one, two, three, or four escape sequences representing the UTF-8 encoding of the character (will only be four escape sequences for characters composed of two &quot;surrogate&quot; characters)." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI" target="_blank"><code>encodeURI()</code></a></li>
<li>] <a title="The encodeURIComponent() method encodes a Uniform Resource Identifier (URI) component by replacing each instance of certain characters by one, two, three, or four escape sequences representing the UTF-8 encoding of the character (will only be four escape sequences for characters composed of two &quot;surrogate&quot; characters)." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent" target="_blank"><code>encodeURIComponent()</code></a></li>
<li>] <a title="The deprecated escape() method computes a new string in which certain characters have been replaced by a hexadecimal escape sequence. Use encodeURI or encodeURIComponent instead." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/escape" target="_blank"><code>escape()</code></a></li>
<li>] <a title="The deprecated unescape() method computes a new string in which hexadecimal escape sequences are replaced with the character that it represents. The escape sequences might be introduced by a function like escape. Because unescape is deprecated, use decodeURI or decodeURIComponent instead." href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/unescape" target="_blank"><code>unescape()</code></a></li>
</ol></ol>
<h2>[WHERE]</h2>
<ol>
<li><strong>]&nbsp;'the global object' exists</strong></li>
<ol>
<li>] on every 'web page' (aka window) that you use</li>
</ol></ol>
<h2>[WHEN]</h2>
<ol>
<li><strong>]&nbsp; you want to use methods that belong to 'the global object' like ...&nbsp;&nbsp;</strong></li>
<ol>
<li>] encoding and decoding url's</li>
</ol>
<li><strong>] you want to create an object variable that is available from anywhere in your code</strong></li>
<ol>
<li>]</li>
</ol></ol>
<h2>[EXAMPLE]</h2>
<ol>
<li>] var numericValue =parseInt("66"); // would return the numberic value of&nbsp;66 from the string value of "66".</li>
</ol>
<h2>[HOW-TO]</h2>
<ol>
<li>] check for undefined</li>
<li>] decodeURI</li>
<li>] encodeURI</li>
</ol>
<h2>[REFERENCE]</h2>
<ol>
<li>] <a href="http://www.w3schools.com/jsref/jsref_obj_global.asp">http://www.w3schools.com/jsref/jsref_obj_global.asp</a>&nbsp;</li>
<li>] <a href="https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects" target="_blank">https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects</a></li>
<li>] <a href="/view/article?id=2692" target="_blank">understanding global</a> - the global object and variables with global scope</li>
</ol>

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