<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >func_get_arg</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REL="HOME" TITLE="PHP 手册" HREF="index.html"><LINK REL="UP" TITLE="Function Handling Functions" HREF="ref.funchand.html"><LINK REL="PREVIOUS" TITLE="create_function" HREF="function.create-function.html"><LINK REL="NEXT" TITLE="func_get_args" HREF="function.func-get-args.html"><META HTTP-EQUIV="Content-type" CONTENT="text/html; charset=UTF-8"></HEAD ><BODY CLASS="refentry" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >PHP 手册</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="function.create-function.html" ACCESSKEY="P" >上一页</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="function.func-get-args.html" ACCESSKEY="N" >下一页</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.func-get-arg" ></A >func_get_arg</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN62769" ></A ><P > (PHP 4, PHP 5)</P >func_get_arg -- Return an item from the argument list</DIV ><DIV CLASS="refsect1" ><A NAME="AEN62772" ></A ><H2 >说明</H2 >mixed <B CLASS="methodname" >func_get_arg</B > ( int arg_num )<BR ></BR ><P > Gets the specified argument from a user-defined function's argument list. </P ><P > This function may be used in conjunction with <A HREF="function.func-get-args.html" ><B CLASS="function" >func_get_args()</B ></A > and <A HREF="function.func-num-args.html" ><B CLASS="function" >func_num_args()</B ></A > to allow user-defined functions to accept variable-length argument lists. </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN62784" ></A ><H2 >参数</H2 ><P > <P ></P ><DIV CLASS="variablelist" ><DL ><DT ><CODE CLASS="parameter" >arg_num</CODE ></DT ><DD ><P > The argument offset. Function arguments are counted starting from zero. </P ></DD ></DL ></DIV > </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN62793" ></A ><H2 >返回值</H2 ><P > Returns the specified argument, or <TT CLASS="constant" ><B >FALSE</B ></TT > on error. </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN62797" ></A ><H2 >错误/异常</H2 ><P > Generates a warning if called from outside of a user-defined function, or if <CODE CLASS="parameter" >arg_num</CODE > is greater than the number of arguments actually passed. </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN62801" ></A ><H2 >范例</H2 ><P > <TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN62804" ></A ><P ><B >例 1. <B CLASS="function" >func_get_arg()</B > example</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br /></font><font color="#007700">function </font><font color="#0000BB">foo</font><font color="#007700">()<br />{<br /> </font><font color="#0000BB">$numargs </font><font color="#007700">= </font><font color="#0000BB">func_num_args</font><font color="#007700">();<br /> echo </font><font color="#DD0000">"Number of arguments: $numargs<br /></font><font color="#007700">\n</font><font color="#DD0000">"</font><font color="#007700">;<br /> if (</font><font color="#0000BB">$numargs </font><font color="#007700">>= </font><font color="#0000BB">2</font><font color="#007700">) {<br /> echo </font><font color="#DD0000">"Second argument is: " </font><font color="#007700">. </font><font color="#0000BB">func_get_arg</font><font color="#007700">(</font><font color="#0000BB">1</font><font color="#007700">) . </font><font color="#DD0000">"<br />\n"</font><font color="#007700">;<br /> }<br />}<br /><br /></font><font color="#0000BB">foo </font><font color="#007700">(</font><font color="#0000BB">1</font><font color="#007700">, </font><font color="#0000BB">2</font><font color="#007700">, </font><font color="#0000BB">3</font><font color="#007700">);<br /></font><font color="#0000BB">?></font> </font> </code></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE > </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN62808" ></A ><H2 >注释</H2 ><DIV CLASS="note" ><BLOCKQUOTE CLASS="note" ><P ><B >注意: </B >Because this function depends on the current scope to determine parameter details, it cannot be used as a function parameter. If you must pass this value, assign the results to a variable, and pass the variable.</P ></BLOCKQUOTE ></DIV ><DIV CLASS="note" ><BLOCKQUOTE CLASS="note" ><P ><B >注意: </B > This function returns a copy of the passed arguments only, and does not account for default (non-passed) arguments. </P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN62814" ></A ><H2 >参见</H2 ><P > <P ></P ><TABLE BORDER="0" ><TBODY ><TR ><TD ><A HREF="function.func-get-args.html" ><B CLASS="function" >func_get_args()</B ></A ></TD ></TR ><TR ><TD ><A HREF="function.func-num-args.html" ><B CLASS="function" >func_num_args()</B ></A ></TD ></TR ></TBODY ></TABLE ><P ></P > </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="function.create-function.html" ACCESSKEY="P" >上一页</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >起始页</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="function.func-get-args.html" ACCESSKEY="N" >下一页</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >create_function</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.funchand.html" ACCESSKEY="U" >上一级</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >func_get_args</TD ></TR ></TABLE ></DIV ></BODY ></HTML >