<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >mysqli_connect</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="MySQLi 扩展库" HREF="ref.mysqli.html"><LINK REL="PREVIOUS" TITLE="mysqli_connect_error" HREF="function.mysqli-connect-error.html"><LINK REL="NEXT" TITLE="mysqli_data_seek" HREF="function.mysqli-data-seek.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.mysqli-connect-error.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.mysqli-data-seek.html" ACCESSKEY="N" >下一页</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.mysqli-connect" ></A >mysqli_connect</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN137914" ></A ><P > (PHP 5)</P >mysqli_connect<P > (no version information, might be only in CVS)</P >mysqli->__construct() -- Open a new connection to the MySQL server</DIV ><DIV CLASS="refsect1" ><A NAME="AEN137918" ></A ><H2 >说明</H2 ><P >Procedural style</P >mysqli <B CLASS="methodname" >mysqli_connect</B > ( [string host [, string username [, string passwd [, string dbname [, int port [, string socket]]]]]] )<BR ></BR ><P >Object oriented style (constructor):</P >class <B CLASS="classname" >mysqli</B > { <BR ></BR ><B CLASS="methodname" >__construct</B > ( [string host [, string username [, string passwd [, string dbname [, int port [, string socket]]]]]] )<BR ></BR >}<P > Opens a connection to the MySQL Server running on. </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN137967" ></A ><H2 >参数</H2 ><P > <P ></P ><DIV CLASS="variablelist" ><DL ><DT ><CODE CLASS="parameter" >host</CODE ></DT ><DD ><P > Can be either a host name or an IP address. Passing the <TT CLASS="constant" ><B >NULL</B ></TT > value or the string "localhost" to this parameter, the local host is assumed. When possible, pipes will be used instead of the TCP/IP protocol. </P ></DD ><DT ><CODE CLASS="parameter" >username</CODE ></DT ><DD ><P > The MySQL user name. </P ></DD ><DT ><CODE CLASS="parameter" >passwd</CODE ></DT ><DD ><P > If provided or <TT CLASS="constant" ><B >NULL</B ></TT >, the MySQL server will attempt to authenticate the user against those user records which have no password only. This allows one username to be used with different permissions (depending on if a password as provided or not). </P ></DD ><DT ><CODE CLASS="parameter" >dbname</CODE ></DT ><DD ><P > If provided will specify the default database to be used when performing queries. </P ></DD ><DT ><CODE CLASS="parameter" >port</CODE ></DT ><DD ><P > Specifies the port number to attempt to connect to the MySQL server. </P ></DD ><DT ><CODE CLASS="parameter" >socket</CODE ></DT ><DD ><P > Specifies the socket or named pipe that should be used. </P ><DIV CLASS="note" ><BLOCKQUOTE CLASS="note" ><P ><B >注意: </B > Specifying the <CODE CLASS="parameter" >socket</CODE > parameter will not explicitly determine the type of connection to be used when connecting to the MySQL server. How the connection is made to the MySQL database is determined by the <CODE CLASS="parameter" >host</CODE > parameter. </P ></BLOCKQUOTE ></DIV ></DD ></DL ></DIV > </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN138007" ></A ><H2 >返回值</H2 ><P > Returns a object which represents the connection to a MySQL Server or <TT CLASS="constant" ><B >FALSE</B ></TT > if the connection failed. </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN138011" ></A ><H2 >范例</H2 ><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN138013" ></A ><P ><B >例 1. Object oriented style</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br />$mysqli </font><font color="#007700">= new </font><font color="#0000BB">mysqli</font><font color="#007700">(</font><font color="#DD0000">"localhost"</font><font color="#007700">, </font><font color="#DD0000">"my_user"</font><font color="#007700">, </font><font color="#DD0000">"my_password"</font><font color="#007700">, </font><font color="#DD0000">"world"</font><font color="#007700">);<br /><br /></font><font color="#FF8000">/* check connection */<br /></font><font color="#007700">if (</font><font color="#0000BB">mysqli_connect_errno</font><font color="#007700">()) {<br /> </font><font color="#0000BB">printf</font><font color="#007700">(</font><font color="#DD0000">"Connect failed: %s\n"</font><font color="#007700">, </font><font color="#0000BB">mysqli_connect_error</font><font color="#007700">());<br /> exit();<br />}<br /><br /></font><font color="#0000BB">printf</font><font color="#007700">(</font><font color="#DD0000">"Host information: %s\n"</font><font color="#007700">, </font><font color="#0000BB">$mysqli</font><font color="#007700">-></font><font color="#0000BB">host_info</font><font color="#007700">);<br /><br /></font><font color="#FF8000">/* close connection */<br /></font><font color="#0000BB">$mysqli</font><font color="#007700">-></font><font color="#0000BB">close</font><font color="#007700">();<br /></font><font color="#0000BB">?></font> </font> </code></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE ><TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN138016" ></A ><P ><B >例 2. Procedural style</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br />$link </font><font color="#007700">= </font><font color="#0000BB">mysqli_connect</font><font color="#007700">(</font><font color="#DD0000">"localhost"</font><font color="#007700">, </font><font color="#DD0000">"my_user"</font><font color="#007700">, </font><font color="#DD0000">"my_password"</font><font color="#007700">, </font><font color="#DD0000">"world"</font><font color="#007700">);<br /><br /></font><font color="#FF8000">/* check connection */<br /></font><font color="#007700">if (!</font><font color="#0000BB">$link</font><font color="#007700">) {<br /> </font><font color="#0000BB">printf</font><font color="#007700">(</font><font color="#DD0000">"Connect failed: %s\n"</font><font color="#007700">, </font><font color="#0000BB">mysqli_connect_error</font><font color="#007700">());<br /> exit();<br />}<br /><br /></font><font color="#0000BB">printf</font><font color="#007700">(</font><font color="#DD0000">"Host information: %s\n"</font><font color="#007700">, </font><font color="#0000BB">mysqli_get_host_info</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">));<br /><br /></font><font color="#FF8000">/* close connection */<br /></font><font color="#0000BB">mysqli_close</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">);<br /></font><font color="#0000BB">?></font> </font> </code></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE ><P >上例将输出:</P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><PRE CLASS="screen" >Host information: Localhost via UNIX socket</PRE ></TD ></TR ></TABLE ></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.mysqli-connect-error.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.mysqli-data-seek.html" ACCESSKEY="N" >下一页</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >mysqli_connect_error</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.mysqli.html" ACCESSKEY="U" >上一级</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >mysqli_data_seek</TD ></TR ></TABLE ></DIV ></BODY ></HTML >