<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >hexdec</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="Math 数学函数" HREF="ref.math.html"><LINK REL="PREVIOUS" TITLE="getrandmax" HREF="function.getrandmax.html"><LINK REL="NEXT" TITLE="hypot" HREF="function.hypot.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.getrandmax.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.hypot.html" ACCESSKEY="N" >下一页</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.hexdec" ></A >hexdec</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN108535" ></A ><P > (PHP 3, PHP 4, PHP 5)</P >hexdec -- 十六进制转换为十进制</DIV ><DIV CLASS="refsect1" ><A NAME="AEN108538" ></A ><H2 >说明</H2 >number <B CLASS="methodname" >hexdec</B > ( string hex_string )<BR ></BR ><P > 返回与 <CODE CLASS="parameter" >hex_string</CODE > 参数所表示的十六进制数等值的的十进制数。<B CLASS="function" >hexdec()</B > 将一个十六进制字符串转换为十进制数。所能转换的最大数值为 7fffffff,即十进制的 2147483647。PHP 4.1.0 开始,该函数可以处理大数字,这种情况下,它会返回 <A HREF="language.types.float.html" ><B CLASS="type" >float</B ></A > 类型。 </P ><P > <B CLASS="function" >hexdec()</B > 将遇到的所有非十六进制字符替换成 <TT CLASS="literal" >0</TT >。这样,所有左边的零都被忽略,但右边的零会计入值中。 <TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN108553" ></A ><P ><B >例 1. <B CLASS="function" >hexdec()</B > 例子</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br />var_dump</font><font color="#007700">(</font><font color="#0000BB">hexdec</font><font color="#007700">(</font><font color="#DD0000">"See"</font><font color="#007700">));<br /></font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">hexdec</font><font color="#007700">(</font><font color="#DD0000">"ee"</font><font color="#007700">));<br /></font><font color="#FF8000">// both print "int(238)"<br /><br /></font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">hexdec</font><font color="#007700">(</font><font color="#DD0000">"that"</font><font color="#007700">)); </font><font color="#FF8000">// print "int(10)"<br /></font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">hexdec</font><font color="#007700">(</font><font color="#DD0000">"a0"</font><font color="#007700">)); </font><font color="#FF8000">// print "int(160)"<br /></font><font color="#0000BB">?></font> </font> </code></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE > </P ><P > 参见 <A HREF="function.dechex.html" ><B CLASS="function" >dechex()</B ></A >,<A HREF="function.bindec.html" ><B CLASS="function" >bindec()</B ></A >,<A HREF="function.octdec.html" ><B CLASS="function" >octdec()</B ></A > 和<A HREF="function.base-convert.html" ><B CLASS="function" >base_convert()</B ></A >。 </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.getrandmax.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.hypot.html" ACCESSKEY="N" >下一页</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >getrandmax</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.math.html" ACCESSKEY="U" >上一级</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >hypot</TD ></TR ></TABLE ></DIV ></BODY ></HTML >