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copied!<p>Use a sequential <code>for</code> loop:</p> <pre><code>var myStringArray = ["Hello","World"]; var arrayLength = myStringArray.length; for (var i = 0; i < arrayLength; i++) { alert(myStringArray[i]); //Do something } </code></pre> <p>@zipcodeman suggests the use of the <code>for...in</code> statement, but for iterating arrays <code>for-in</code> should be avoided, that statement is meant to <strong>enumerate</strong> object properties.</p> <p>It shouldn't be used for array-like objects because:</p> <ul> <li>The order of iteration is not guaranteed, the array indexes may not be visited in numeric order.</li> <li>Inherited properties are also enumerated.</li> </ul> <p>The second point is that it can give you a lot of problems, for example, if you extend the <code>Array.prototype</code> object to include a method there, that property will be also enumerated.</p> <p>For example:</p> <pre><code>Array.prototype.foo = "foo!"; var array = ['a', 'b', 'c']; for (var i in array) { alert(array[i]); } </code></pre> <p>The above code will alert, "a", "b", "c" and "foo!".</p> <p>That be particularly a problem if you use some library that relies heavily on native prototypes augmention (such as MooTools for example).</p> <p>The <code>for-in</code> statement as I said before is there to <em>enumerate</em> object properties, for example:</p> <pre><code>var obj = { "a": 1, "b": 2, "c": 3 }; for (var prop in obj) { if (obj.hasOwnProperty(prop)) { // or if (Object.prototype.hasOwnProperty.call(obj,prop)) for safety... alert("prop: " + prop + " value: " + obj[prop]) } } </code></pre> <p>In the above example the <code>hasOwnProperty</code> method allows you to enumerate only <em>own properties</em>, that's it, only the properties that the object physically has, no inherited properties.</p> <p>I would recommend you to read the following article:</p> <ul> <li><a href="http://web.archive.org/web/20101213150231/http://dhtmlkitchen.com/?category=/JavaScript/&date=2007/10/21/&entry=Iteration-Enumeration-Primitives-and-Objects" rel="noreferrer">Enumeration VS Iteration</a></li> </ul>

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