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<p><b>Новая страница</b></p><div>== Append element to the end of an Array by reference the Array.length property==<br />
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<title>Append element to the end of an Array</title><br />
<script language="javascript" type="text/javascript"><br />
<!--<br />
var x = new Array(2,3,4);<br />
x[x.length] = 1;<br />
alert(x);<br />
//--><br />
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== Array.length==<br />
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<p>The length property holds the number of elements in the array.</p><br />
<p>This property is a read/write variable.</p><br />
<p>The size of an array can change dynamically at any time.</p><br />
<p>The length of the array can also be changed by altering the length attribute.</p><br />
<p>If the length property is overwritten with a number that is larger than the original number, new elements are added to the end of the array and assigned undefined values.</p><br />
<p>If the length property is overwritten with a number that is smaller than the original number, elements at the end of the array are lost.</p><br />
<p>If the length of an array is originally 10 and is reduced to 5, the elements in position 6 through 10 are lost.</p><br />
<p>The following example uses the length Property to Reduce the Number of Elements in an Array.</p><br />
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<script language="JavaScript"><br />
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coins = new Array("A","B","C","D");<br />
x = coins.length; <br />
coins.length = 3 <br />
document.write("The coins array contains: ", coins.join(","));<br />
--><br />
</script><br />
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== Get Array length==<br />
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<title>Get Array length</title><br />
<script language="javascript" type="text/javascript"><br />
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var x = new Array(2,3,4);<br />
alert(x.length);<br />
//--><br />
</script><br />
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== Get the last element in an Array==<br />
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<title>Get the last element in an Array</title><br />
<script language="javascript" type="text/javascript"><br />
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var x = new Array(2,3,4);<br />
alert(x[x.length-1]);<br />
//--><br />
</script><br />
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== Length Automatically Updates==<br />
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<title>Length Automatically Updates</title><br />
<script language="javascript" type="text/javascript"><br />
<!--<br />
var someArray = new Array();<br />
alert(someArray.length);<br />
someArray[0] = "A";<br />
alert(someArray.length);<br />
someArray[1] = "B";<br />
alert(someArray.length);<br />
//--><br />
</script><br />
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<h1>Length Automatically Updates</h1><br />
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== Remove elements from array by changing the array length==<br />
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<title>Removing Elements</title><br />
<script language="javascript" type="text/javascript"><br />
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var x = new Array(0,1,2,3,4);<br />
var firstElement = x[x.length-1];<br />
x.length = x.length-1;<br />
var secondElement = x[x.length-1];<br />
x.length = x.length-1;<br />
alert(firstElement)<br />
alert(secondElement)<br />
alert(x);<br />
//--><br />
</script><br />
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<h1>Removing Elements</h1><br />
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