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Converted to HTML in WebWorks Publisher 2000. manual wdt 1.5"> <META NAME="LASTUPDATED" CONTENT="09/28/00 13:15:58"> <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="regexp.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="sun.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="String"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="5"><B><zrefhead1>String</zrefhead1></B></FONT><P><A NAME="1193173"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>An object representing a series of characters in a string. <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="1193141"> </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="1193145"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext><I>Implemented in</I></ztabletext></FONT> </TD> <TD VALIGN=TOP><P><A NAME="1193147"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>JavaScript 1.0: Create a <FONT FACE="courier, couriernew, monospaced size">String</FONT> object only by quoting characters.</ztabletext></FONT><P><A NAME="1199831"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext></ztabletext></FONT><P><A NAME="1199852"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>JavaScript 1.1, NES 2.0: added <FONT FACE="courier, couriernew, monospaced size">String</FONT> constructor; added <FONT FACE="courier, couriernew, monospaced size">prototype</FONT> property; added <A HREF="string.html#1194452" >split</A> method; added ability to pass strings among scripts in different windows or frames (in previous releases, you had to add an empty string to another window's string to refer to it).</ztabletext></FONT><P><A NAME="1199832"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext></ztabletext></FONT><P><A NAME="1199861"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>JavaScript 1.2, NES 3.0: added <A HREF="string.html#1196678" >concat</A>, <A HREF="string.html#1205239" >match</A>, <A HREF="string.html#1194258" >replace</A>, <A HREF="string.html#1194332" >search</A>, <A HREF="string.html#1194366" >slice</A>, and <A HREF="string.html#1194618" >substr</A> methods.</ztabletext></FONT><P><A NAME="1193172"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext></ztabletext></FONT><P><A NAME="1199870"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>JavaScript 1.3: added <A HREF="string.html#1194796" >toSource</A> method; changed <A HREF="string.html#1196647" >charCodeAt</A>, <A HREF="string.html#1225094" >fromCharCode</A>, and <A HREF="string.html#1194258" >replace</A> methods.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><P><A NAME="1203114"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext><I>ECMA version</I></ztabletext></FONT> </TD> <TD VALIGN=TOP><P><A NAME="1203116"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>ECMA-262</ztabletext></FONT> </TD> </TR></TABLE><P></zparagraph></FONT><P><BR><A NAME="1199477"> </A><A NAME="Created by"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Created by</zrefheader></B></FONT><BR><A NAME="1193175"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The <FONT FACE="courier, couriernew, monospaced size">String</FONT> constructor:</zparagraph></FONT><P><A NAME="1193176"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>new String(<I>string</I>)</zcodeline></FONT><P><BR><A NAME="1193177"> </A><A NAME="Parameters"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Parameters</zrefheader></B></FONT><BR><A NAME="1193183"> </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="1193180"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>string</zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193182"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Any string.</ztabletext></FONT> </TD> </TR></TABLE><P></zparagraph></FONT><P><BR><A NAME="1193184"> </A><A NAME="Description"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Description</zrefheader></B></FONT><BR><A NAME="1228794"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>The <FONT FACE="courier, couriernew, monospaced size">String</FONT> object is a wrapper around the string primitive data type. Do not confuse a string literal with the <FONT FACE="courier, couriernew, monospaced size">String</FONT> object. For example, the following code creates the string literal <FONT FACE="courier, couriernew, monospaced size">s1</FONT> and also the <FONT FACE="courier, couriernew, monospaced size">String</FONT> object <FONT FACE="courier, couriernew, monospaced size">s2</FONT>:</zparagraph></FONT><P><A NAME="1228795"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>s1 = "foo" // creates a string literal value<br>s2 = new String("foo") // creates a String object</zcodeline></FONT><P><A NAME="1228796"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>You can call any of the methods of the <FONT FACE="courier, couriernew, monospaced size">String</FONT> object on a string literal value—JavaScript automatically converts the string literal to a temporary <FONT FACE="courier, couriernew, monospaced size">String</FONT> object, calls the method, then discards the temporary <FONT FACE="courier, couriernew, monospaced size">String</FONT> object. You can also use the <FONT FACE="courier, couriernew, monospaced size">String.length</FONT> property with a string literal.</zparagraph></FONT><P><A NAME="1237619"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>You should use string literals unless you specifically need to use a <FONT FACE="courier, couriernew, monospaced size">String</FONT> object, because <FONT FACE="courier, couriernew, monospaced size">String</FONT> objects can have counterintuitive behavior. For example:</zparagraph></FONT><P><A NAME="1237620"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline>s1 = "2 + 2" // creates a string literal value<br>s2 = new String("2 + 2") // creates a String object<br>eval(s1) // returns the number 4<br>eval(s2) // returns the string "2 + 2"</zcodeline></FONT><P><A NAME="1193186"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>A string can be represented as a literal enclosed by single or double quotation marks; for example, "Netscape" or `Netscape'.</zparagraph></FONT><P><A NAME="1228443"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><zparagraph>You can convert the value of any object into a string using the top-level <A HREF="toplev.html#1064506" >String</A> function.</zparagraph></FONT><P><BR><A NAME="1193187"> </A><A NAME="Property Summary"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Property Summary</zrefheader></B></FONT><BR><A NAME="1193207"> </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 BGCOLOR="#CCCCCC" ALIGN=LEFT VALIGN=TOP> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193190"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Property</ztablehead></B></FONT></TH> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193192"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Description</ztablehead></B></FONT></TH> </DIV></TR> <TR> <TD VALIGN=TOP><A NAME="1214599"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1214362" >constructor</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1214601"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Specifies the function that creates an object's prototype.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1193197"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1193437" >length</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193199"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Reflects the length of the string.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1193204"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1193463" >prototype</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193206"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Allows the addition of properties to a <FONT FACE="courier, couriernew, monospaced size">String</FONT> object.</ztabletext></FONT> </TD> </TR></TABLE><P></zparagraph></FONT><P><BR><A NAME="1193208"> </A><A NAME="Method Summary"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><zrefheader>Method Summary</zrefheader></B></FONT><BR><A NAME="1193420"> </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 BGCOLOR="#CCCCCC" ALIGN=LEFT VALIGN=TOP> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193211"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Method</ztablehead></B></FONT></TH> <TH VALIGN=TOP ALIGN=LEFT><A NAME="1193213"> </A><P ALIGN="LEFT"><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><B><ztablehead>Description</ztablehead></B></FONT></TH> </DIV></TR> <TR> <TD VALIGN=TOP><A NAME="1193218"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1196382" >anchor</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193220"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Creates an HTML anchor that is used as a hypertext target.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1193225"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1196447" >big</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193227"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Causes a string to be displayed in a big font as if it were in a <FONT FACE="courier, couriernew, monospaced size">BIG</FONT> tag.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1193232"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1196495" >blink</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193234"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Causes a string to blink as if it were in a <FONT FACE="courier, couriernew, monospaced size">BLINK</FONT> tag.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1193239"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1196546" >bold</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP><P><A NAME="1193241"> </A><FONT FACE="Arial, Helvetica, sans-serif" SIZE="2"><ztabletext>Causes a string to be displayed as if it were in a <FONT FACE="courier, couriernew, monospaced size">B</FONT> tag.</ztabletext></FONT> </TD> </TR> <TR> <TD VALIGN=TOP><A NAME="1193246"></A><FONT FACE="courier, couriernew, monospaced size" SIZE="2"><zcodeline><A HREF="string.html#1196596" >charAt</A></zcodeline></FONT><P> </TD> <TD VALIGN=TOP>⌨️ 快捷键说明
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