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POValid javascript object property names
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copied!<p>I'm trying to work out what is considered valid for the property name of a javascript object. For example</p> <pre><code>var b = {} b['-^colour'] = "blue"; // Works fine in Firefox, Chrome, Safari b['colour'] = "green"; // Ditto alert(b['-^colour']); // Ditto alert(b.colour); // Ditto for(prop in b) alert(prop); // Ditto //alert(b.-^colour); // Fails (expected) </code></pre> <p>This <a href="https://stackoverflow.com/questions/1661197/valid-characters-for-javascript-variable-names">post</a> details valid javascript variable names, and '-^colour' is clearly not valid (as a variable name). Does the same apply to object property names? Looking at the above I'm trying to work out if</p> <ol> <li><p>b['-^colour'] is invalid, but works in all browsers by quirk, and I shouldn't trust it to work going forward</p></li> <li><p>b['-^colour'] is completely valid, but it's just of a form that can only be accessed in this manner - (it's supported so Objects can be used as maps perhaps?)</p></li> <li><p>Something else</p></li> </ol> <p>As an aside, a global variable in javascript might be declared at the top level as</p> <pre><code>var abc = 0; </code></pre> <p>but could also be created (as I understand it) with </p> <pre><code>window['abc'] = 0; </code></pre> <p>the following works in all the above browsers</p> <pre><code>window['@£$%'] = "bling!"; alert(window['@£$%']); </code></pre> <p>Is this valid? It seems to contradict the variable naming rules - or am I not declaring a variable there? What's the difference between a variable and an object property name?</p>

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