<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >is_numeric</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="Variable 变量函数" HREF="ref.var.html"><LINK REL="PREVIOUS" TITLE="is_null" HREF="function.is-null.html"><LINK REL="NEXT" TITLE="is_object" HREF="function.is-object.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.is-null.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.is-object.html" ACCESSKEY="N" >下一页</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.is-numeric" ></A >is_numeric</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN236683" ></A ><P > (PHP 4, PHP 5)</P >is_numeric -- 检测变量是否为数字或数字字符串 </DIV ><DIV CLASS="refsect1" ><A NAME="AEN236686" ></A ><H2 >描述</H2 >bool <B CLASS="methodname" >is_numeric</B > ( mixed var )<BR ></BR ><P > 如果 <CODE CLASS="parameter" >var</CODE > 是数字和数字字符串则返回 <TT CLASS="constant" ><B >TRUE</B ></TT >,否则返回 <TT CLASS="constant" ><B >FALSE</B ></TT >。 </P ><P > 参见 <A HREF="function.is-bool.html" ><B CLASS="function" >is_bool()</B ></A >、<A HREF="function.is-float.html" ><B CLASS="function" >is_float()</B ></A >、<A HREF="function.is-int.html" ><B CLASS="function" >is_int()</B ></A >、<A HREF="function.is-string.html" ><B CLASS="function" >is_string()</B ></A >、<A HREF="function.is-object.html" ><B CLASS="function" >is_object()</B ></A >、<A HREF="function.is-array.html" ><B CLASS="function" >is_array()</B ></A > 和 <A HREF="function.is-integer.html" ><B CLASS="function" >is_integer()</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.is-null.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.is-object.html" ACCESSKEY="N" >下一页</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >is_null</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.var.html" ACCESSKEY="U" >上一级</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >is_object</TD ></TR ></TABLE ></DIV ></BODY ></HTML >