Newbie needs help with Arrays

@fredmvNov 03.2003 — #
[size=3]&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"&gt;
 
 &lt;html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"&gt;
 &lt;head&gt;
 &lt;title&gt;untitled&lt;/title&gt;
 &lt;meta http-equiv="Content-Type" content="application/xhtml+xml; charset=iso-8859-1" /&gt;
 &lt;script type="text/javascript"&gt;
 //&lt;![CDATA[
 [color=blue]/*
 First, create a new array using the Array constructor and store
 it in a variable called [b]theArray[/b].
 */[/color]
 var theArray = new Array();
 
 <i>	</i>		[color=blue]/*
 <i>	</i>			Now we need to prompt the user for a number, we can do this using the prompt method.
 <i>	</i>			This number will be the length of the array.
 <i>	</i>		*/[/color]
 <i>	</i>		var sizeOfArray = parseInt(prompt("How many items will the array have?", ""));
 
 <i>	</i>		[color=blue]/*
 <i>	</i>			This next line may look complex, but once you understand what is going on, it is actually
 <i>	</i>			quite simple. This is called a for loop and is a control structure in JavaScript (and many other
 <i>	</i>			programming languages, for that matter). Alright, so lets look at the first part:
 <i>	</i>				[b]for(i=0;[/b]
 <i>	</i>			This is generally referred to as the [i]initalization[/i] stage of the loop. This tells the loop
 <i>	</i>			to start off at zero. Now that the variable [b]i[/b] is defined as 0, we can now work with it.
 
 <i>	</i>			Now for the next part of the for loop:
 <i>	</i>				[b]i&lt;sizeOfArray;[/b]
 <i>	</i>			This line almost explains itself - keep doing everything after the curleybrace until [b]i[/b] is
 <i>	</i>			less than the [b]sizeOfArray[/b] variable. Remember that we previously prompted the user to enter
 <i>	</i>			a value for this variable, the loop will keep comparing the value that was entered and stored in the
 <i>	</i>			[b]sizeOfArray[/b] variable to the current state of the [b]i[/b] variable.
 
 <i>	</i>			Finally, the last part of the for loop:
 <i>	</i>				[b]i++)[/b]
 <i>	</i>			What this does is [i]increment[/i] the current value of the [b]i[/b] variable. The term [i]increment[/i]
 <i>	</i>			is just another way of saying [i]adding 1 to[/i]. 
 
 <i>	</i>			And that's all there really is to a for loop. 
 <i>	</i>		*/[/color] 
 <i>	</i>		for(i=0; i&lt;sizeOfArray; i++)
 <i>	</i>		{
 <i>	</i>			[color=blue]/*
 <i>	</i>				You see how in the loop, we keep [i]incrementing[/i] the value of the [b]i[/b] variable? What we're doing
 <i>	</i>				here is setting the current cell of the array to whatever [b]i[/b] is currently equal to. For the value of
 <i>	</i>				this specific cell, we're using the [b]prompt[/b] method again to ask for some user input.
 <i>	</i>			*/[/color]
 <i>	</i>			theArray[i] = prompt( "What will the value be for cell number " + i + "?", "" );
 <i>	</i>		}
 
 <i>	</i>		[color=blue]/*
 <i>	</i>			Here we go again with the for loop. The exact same idea is used here.
 <i>	</i>		*/[/color]
 <i>	</i>		for(i=0; i&lt;theArray.length; i++)
 <i>	</i>		{
 <i>	</i>			[color=blue]/*
 <i>	</i>				Now we're using the [b]document[/b] object's [b]writeln[/b] method. It works just like the [b]write[/b]
 <i>	</i>				method except for one small difference - it appends a newline ([b]n[/b]) character to the end of the output.
 
 <i>	</i>				All we're doing here is going through every cell in the array and printing its value and then using a break ([b]&lt;br /&gt;[/b])
 <i>	</i>				to display each array cell value on its own line.
 <i>	</i>			*/[/color]
 <i>	</i>			document.writeln("theArray[" + i + "] = " + theArray[i] + "&lt;br /&gt;");
 <i>	</i>		}
 <i>	</i>		[color=blue]/*
 <i>	</i>			And we're done! I hope that clears things up for you.
 <i>	</i>		*/[/color]
 <i>	</i>	//]]&gt;
 <i>	</i>	&lt;/script&gt;
 <i>	</i>&lt;/head&gt;
 <i>	</i>&lt;body&gt;&lt;/body&gt;
 &lt;/html&gt;[/size]
Newbie needs help with Arrays

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