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Converted to HTML in WebWorks Publisher 2000. manual wdt 1.5"> <META NAME="LASTUPDATED" CONTENT="09/28/00 13:15:07"> <TITLE> Core JavaScript Reference 1.5: </TITLE></HEAD><BODY TEXT="#000000" LINK="#666699" VLINK="#666699" ALINK="#333366" BGCOLOR="#FFFFFF"><MAINCONTENT><NAVIGATIONCONTENT> <TABLE WIDTH="100%" BORDER="0" CELLSPACING="4"> <TR> <TD VALIGN="TOP"> <b><a href="objintro.html"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2" COLOR="#993300">Previous</a></FONT> </b><a href="contents.html"><b><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2" COLOR="#993300">Contents</a></FONT></b> <a href="ix.html"><b><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2" COLOR="#993300">Index</a></FONT></b> <a href="boolean.html"><b><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2" COLOR="#993300">Next</a></FONT></b> </TD> </TR> <TR> <TD VALIGN="TOP" ALIGN="RIGHT" BGCOLOR="#CCCCCC"> <FONT FACE="Arial, Helvetica, sans-serif" COLOR="#000000" SIZE="2"><B> Core JavaScript Reference 1.5</B></FONT> </TD> </TR> <TR> </TABLE> <BR></NAVIGATIONCONTENT><BOOKCONTENT> <blockquote><BR><BR> <BR><BR><P><A NAME="1193137"> </A><A NAME="Array"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="5"><B><zrefhead1>Array</zrefhead1></B></FONT><P><A NAME="1193151"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>Lets you work with arrays.<BR><P><TABLE WIDTH="90%" BORDER="1" CELLPADDING="5" CELLSPACING="0"> <CAPTION></CAPTION><P><FONT FACE=""><B></B></FONT><BR><BR> <TR> <TD VALIGN=TOP COLSPAN=2 ROWSPAN=1><P><A NAME="1193140"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext><I>Core object</I></ztabletext></FONT></TD> </TR> <TR> <TD VALIGN=TOP><P><A NAME="1193144"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext><I>Implemented in</I></ztabletext></FONT> </TD> <TD VALIGN=TOP><P><A NAME="1193146"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>JavaScript 1.1, NES 2.0</ztabletext></FONT><P><A NAME="1198127"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext></ztabletext></FONT><P><A NAME="1193150"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>JavaScript 1.3: added <A HREF="array.html#1193889" >toSource</A> method; changed <A HREF="array.html#1193439" >length</A> property; changed <A HREF="array.html#1196550" >push</A> method</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><P><A NAME="1198268"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext><I>ECMA version</I></ztabletext></FONT> </TD> <TD VALIGN=TOP><P><A NAME="1198270"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>ECMA-262</ztabletext></FONT> </TD> </TR></TABLE><P></zparagraph></FONT><P><BR><A NAME="1193152"> </A><A NAME="Created by"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Created by</zrefheader></B></FONT><BR><A NAME="1193153"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The <FONT FACE="courier, couriernew, monospaced size">Array</FONT> object constructor:</zparagraph></FONT><P><A NAME="1193154"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>new Array(<I>arrayLength</I>)<br>new Array(<I>element0</I>, <I>element1</I>, ..., <I>elementN</I>)</zcodeline></FONT><P><A NAME="1213845"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>An array literal:</zparagraph></FONT><P><A NAME="1213846"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>[<I>element0</I>, <I>element1</I>, ..., <I>elementN</I>]</zcodeline></FONT><P><A NAME="1213847"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph><I>JavaScript 1.2 when you specify </I><FONT FACE="courier, couriernew, monospaced size"><I>LANGUAGE="JavaScript1.2"</I></font><I> in the </I><FONT FACE="courier, couriernew, monospaced size"><I><SCRIPT></I></font><I> tag:</I></zparagraph></FONT><P><A NAME="1193156"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>new Array(<I>element0</I>, <I>element1</I>, ..., <I>elementN</I>)</zcodeline></FONT><P><A NAME="1193157"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph><I>JavaScript 1.2 when you do not specify </I><FONT FACE="courier, couriernew, monospaced size"><I>LANGUAGE="JavaScript1.2"</I></font><I> in the </I><FONT FACE="courier, couriernew, monospaced size"><I><SCRIPT></I></font><I> tag:</I></zparagraph></FONT><P><A NAME="1193158"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>new Array([<I>arrayLength</I>])<br>new Array([<I>element0</I>[, <I>element1</I>[, ..., <I>elementN</I>]]])</zcodeline></FONT><P><A NAME="1193159"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph><I>JavaScript 1.1:</I></zparagraph></FONT><P><A NAME="1193160"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>new Array([<I>arrayLength</I>])<br>new Array([<I>element0</I>[, <I>element1</I>[, ..., <I>elementN</I>]]])</zcodeline></FONT><P><BR><A NAME="1193162"> </A><A NAME="Parameters"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Parameters</zrefheader></B></FONT><BR><A NAME="1211883"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph><BR><P><TABLE WIDTH="90%" BORDER="1" CELLPADDING="5" CELLSPACING="0"> <CAPTION></CAPTION><P><FONT FACE=""><B></B></FONT><BR><BR> <TR> <TD VALIGN=TOP><A NAME="1211876"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>arrayLength</zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1211878"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>The initial length of the array. You can access this value using the <FONT FACE="courier, couriernew, monospaced size">length</FONT> property. If the value specified is not a number, an array of length 1 is created, with the first element having the specified value. The maximum length allowed for an array is 4,294,967,295.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1211880"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>element<I>N</I></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1211882"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>A list of values for the array's elements. When this form is specified, the array is initialized with the specified values as its elements, and the array's <FONT FACE="courier, couriernew, monospaced size">length</FONT> property is set to the number of arguments.</ztabletext></FONT> </TD> </TR></TABLE><P></zparagraph></FONT><P><BR><A NAME="1211884"> </A><A NAME="Description"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Description</zrefheader></B></FONT><BR><A NAME="1211904"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>An array is an ordered set of values associated with a single variable name.</zparagraph></FONT><P><A NAME="1212668"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The following example creates an <FONT FACE="courier, couriernew, monospaced size">Array</FONT> object with an array literal; the <FONT FACE="courier, couriernew, monospaced size">coffees</FONT> array contains three elements and a length of three:</zparagraph></FONT><P><A NAME="1212669"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>coffees = ["French Roast", "Columbian", "Kona"]</zcodeline></FONT><P><A NAME="1217769"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>You can construct a <I>dense</I> array of two or more elements starting with index 0 if you define initial values for all elements. A dense array is one in which each element has a value. The following code creates a dense array with three elements:</zparagraph></FONT><P><A NAME="1217770"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>myArray = new Array("Hello", myVar, 3.14159)</zcodeline></FONT><P><P><A NAME="1211905"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zheadrunin>Indexing an array. </zheadrunin></B></FONT><A NAME="1211907"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>You index an array by its ordinal number. For example, assume you define the following array:</zparagraph></FONT><P><A NAME="1193177"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>myArray = new Array("Wind","Rain","Fire")</zcodeline></FONT><P><A NAME="1204385"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>You then refer to the first element of the array as <FONT FACE="courier, couriernew, monospaced size">myArray[0]</FONT> and the second element of the array as <FONT FACE="courier, couriernew, monospaced size">myArray[1]</FONT>.</zparagraph></FONT><P><P><A NAME="1204386"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zheadrunin>Specifying a single parameter. </zheadrunin></B></FONT><A NAME="1204388"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>When you specify a single numeric parameter with the <FONT FACE="courier, couriernew, monospaced size">Array</FONT> constructor, you specify the initial length of the array. The following code creates an array of five elements:</zparagraph></FONT><P><A NAME="1193182"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>billingMethod = new Array(5)</zcodeline></FONT><P><A NAME="1193183"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The behavior of the <FONT FACE="courier, couriernew, monospaced size">Array</FONT> constructor depends on whether the single parameter is a number.</zparagraph></FONT><P><ul><A NAME="1193185"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B> <li></B><zsmartlist1>If the value specified is a number, the constructor converts the number to an unsigned, 32-bit integer and generates an array with the <FONT FACE="courier, couriernew, monospaced size">length</FONT> property (size of the array) set to the integer. The array initially contains no elements, even though it might have a non-zero length.</zsmartlist1></FONT><P><A NAME="1193186"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B> <li></B><zsmartlist1>If the value specified is not a number, an array of length 1 is created, with the first element having the specified value.</zsmartlist1></FONT><P></ul><A NAME="1193188"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The following code creates an array of length 25, then assigns values to the first three elements:</zparagraph></FONT><P><A NAME="1193189"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>musicTypes = new Array(25)<br>musicTypes[0] = "R&B"<br>musicTypes[1] = "Blues"<br>musicTypes[2] = "Jazz"</zcodeline></FONT><P><P><A NAME="1193193"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zheadrunin>Increasing the array length indirectly. </zheadrunin></B></FONT><A NAME="1193195"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>An array's length increases if you assign a value to an element higher than the current length of the array. The following code creates an array of length 0, then assigns a value to element 99. This changes the length of the array to 100.</zparagraph></FONT><P><A NAME="1204395"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>colors = new Array()<br>colors[99] = "midnightblue"</zcodeline></FONT><P><P><A NAME="1204396"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zheadrunin>Creating an array using the result of a match. </zheadrunin></B></FONT><A NAME="1204397"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The result of a match between a regular expression and a string can create an array. This array has properties and elements that provide information about the match. An array is the return value of <A HREF="regexp.html#1194735" >RegExp.exec</A>, <A HREF="string.html#1205239" >String.match</A>, and <A HREF="string.html#1194258" >String.replace</A>. To help explain these properties and elements, look at the following example and then refer to the table below: </zparagraph></FONT><P><A NAME="1193208"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><SCRIPT LANGUAGE="JavaScript1.2"><br>//Match one d followed by one or more b's followed by one d<br>//Remember matched b's and the following d<br>//Ignore case</zcodeline></FONT><P><A NAME="1193209"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>myRe=/d(b+)(d)/i;<br>myArray = myRe.exec("cdbBdbsbz");</zcodeline></FONT><P><A NAME="1193210"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline></SCRIPT></zcodeline></FONT><P><A NAME="1193211"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The properties and elements returned from this match are as follows:</zparagraph></FONT><P><P><A NAME="1193243"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><BR><P><TABLE WIDTH="90%" BORDER="1" CELLPADDING="5" CELLSPACING="0"> <CAPTION></CAPTION><P><FONT FACE=""><B></B></FONT><BR><BR> <TR BGCOLOR="#CCCCCC" ALIGN=LEFT VALIGN=TOP> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193214"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Property/Element</ztablehead></B></FONT></TH> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193216"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Description</ztablehead></B></FONT></TH> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193218"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Example</ztablehead></B></FONT></TH> </DIV></TR> <TR> <TD VALIGN=TOP><A NAME="1193220"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>input</zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193222"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>A read-only property that reflects the original string against which the regular expression was matched.</ztabletext></FONT> </TD> <TD VALIGN=TOP><P><A NAME="1193224"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>cdbBdbsbz</ztabletext></FONT> </TD>?? 快捷鍵說明
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