<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >mysql_data_seek</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="MySQL 函数" HREF="ref.mysql.html"><LINK REL="PREVIOUS" TITLE="mysql_create_db" HREF="function.mysql-create-db.html"><LINK REL="NEXT" TITLE="mysql_db_name" HREF="function.mysql-db-name.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.mysql-create-db.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.mysql-db-name.html" ACCESSKEY="N" >下一页</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.mysql-data-seek" ></A >mysql_data_seek</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN135133" ></A ><P > (PHP 3, PHP 4, PHP 5)</P >mysql_data_seek -- 移动内部结果的指针</DIV ><DIV CLASS="refsect1" ><A NAME="AEN135136" ></A ><H2 >说明</H2 >bool <B CLASS="methodname" >mysql_data_seek</B > ( resource result, int row_number )<BR ></BR ><P > <B CLASS="function" >mysql_data_seek()</B > 将指定的结果标识所关联的 MySQL 结果内部的行指针移动到指定的行号。接着调用 <A HREF="function.mysql-fetch-row.html" ><B CLASS="function" >mysql_fetch_row()</B ></A > 将返回那一行。 </P ><P > <CODE CLASS="parameter" >row_number</CODE > 从 0 开始。<CODE CLASS="parameter" >row_number</CODE > 的取值范围应该从 0 到 mysql_num_rows - 1。但是如果结果集为空(<A HREF="function.mysql-num-rows.html" ><B CLASS="function" >mysql_num_rows()</B ></A > == 0),要将指针移动到 0 会失败并发出 <A HREF="ref.errorfunc.html#e-warning" >E_WARNING</A > 级的错误,<B CLASS="function" >mysql_data_seek()</B > 将返回 <TT CLASS="constant" ><B >FALSE</B ></TT >。 </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN135157" ></A ><H2 >参数</H2 ><P > <P ></P ><DIV CLASS="variablelist" ><DL ><DT ><CODE CLASS="parameter" > result</CODE ></DT ><DD ><P >返回类型为 <A HREF="language.types.resource.html" ><B CLASS="type" >resource</B ></A > 的结果集。该结果集从 <A HREF="function.mysql-query.html" ><B CLASS="function" >mysql_query()</B ></A > 的调用中得到。</P ></DD ><DT ><CODE CLASS="parameter" >row_number</CODE ></DT ><DD ><P > 想要设定的新的结果集指针的行数。 </P ></DD ></DL ></DIV > </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN135173" ></A ><H2 >返回值</H2 ><P > 如果成功则返回 <TT CLASS="constant" ><B >TRUE</B ></TT >,失败则返回 <TT CLASS="constant" ><B >FALSE</B ></TT >。 </P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN135178" ></A ><H2 >范例</H2 ><P > <TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN135181" ></A ><P ><B >例 1. <B CLASS="function" >mysql_data_seek()</B > 例子</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br />$link </font><font color="#007700">= </font><font color="#0000BB">mysql_connect</font><font color="#007700">(</font><font color="#DD0000">'localhost'</font><font color="#007700">, </font><font color="#DD0000">'mysql_user'</font><font color="#007700">, </font><font color="#DD0000">'mysql_password'</font><font color="#007700">);<br />if (!</font><font color="#0000BB">$link</font><font color="#007700">) {<br /> die(</font><font color="#DD0000">'Could not connect: ' </font><font color="#007700">. </font><font color="#0000BB">mysql_error</font><font color="#007700">());<br />}<br /></font><font color="#0000BB">$db_selected </font><font color="#007700">= </font><font color="#0000BB">mysql_select_db</font><font color="#007700">(</font><font color="#DD0000">'sample_db'</font><font color="#007700">);<br />if (!</font><font color="#0000BB">$db_selected</font><font color="#007700">) {<br /> die(</font><font color="#DD0000">'Could not select database: ' </font><font color="#007700">. </font><font color="#0000BB">mysql_error</font><font color="#007700">());<br />}<br /></font><font color="#0000BB">$query </font><font color="#007700">= </font><font color="#DD0000">'SELECT last_name, first_name FROM friends'</font><font color="#007700">;<br /></font><font color="#0000BB">$result </font><font color="#007700">= </font><font color="#0000BB">mysql_query</font><font color="#007700">(</font><font color="#0000BB">$query</font><font color="#007700">);<br />if (!</font><font color="#0000BB">$result</font><font color="#007700">) {<br /> die(</font><font color="#DD0000">'Query failed: ' </font><font color="#007700">. </font><font color="#0000BB">mysql_error</font><font color="#007700">());<br />}<br /></font><font color="#FF8000">/* fetch rows in reverse order */<br /></font><font color="#007700">for (</font><font color="#0000BB">$i </font><font color="#007700">= </font><font color="#0000BB">mysql_num_rows</font><font color="#007700">(</font><font color="#0000BB">$result</font><font color="#007700">) - </font><font color="#0000BB">1</font><font color="#007700">; </font><font color="#0000BB">$i </font><font color="#007700">>= </font><font color="#0000BB">0</font><font color="#007700">; </font><font color="#0000BB">$i</font><font color="#007700">--) {<br /> if (!</font><font color="#0000BB">mysql_data_seek</font><font color="#007700">(</font><font color="#0000BB">$result</font><font color="#007700">, </font><font color="#0000BB">$i</font><font color="#007700">)) {<br /> echo </font><font color="#DD0000">"Cannot seek to row $i: " </font><font color="#007700">. </font><font color="#0000BB">mysql_error</font><font color="#007700">() . </font><font color="#DD0000">"\n"</font><font color="#007700">;<br /> continue;<br /> }<br /><br /> if (!(</font><font color="#0000BB">$row </font><font color="#007700">= </font><font color="#0000BB">mysql_fetch_assoc</font><font color="#007700">(</font><font color="#0000BB">$result</font><font color="#007700">))) {<br /> continue;<br /> }<br /><br /> echo </font><font color="#0000BB">$row</font><font color="#007700">[</font><font color="#DD0000">'last_name'</font><font color="#007700">] . </font><font color="#DD0000">' ' </font><font color="#007700">. </font><font color="#0000BB">$row</font><font color="#007700">[</font><font color="#DD0000">'first_name'</font><font color="#007700">] . </font><font color="#DD0000">"<br />\n"</font><font color="#007700">;<br />}<br /><br /></font><font color="#0000BB">mysql_free_result</font><font color="#007700">(</font><font color="#0000BB">$result</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="AEN135185" ></A ><H2 >注释</H2 ><DIV CLASS="note" ><BLOCKQUOTE CLASS="note" ><P ><B >注意: </B > <B CLASS="function" >mysql_data_seek()</B > 只能和 <A HREF="function.mysql-query.html" ><B CLASS="function" >mysql_query()</B ></A > 结合起来使用,而不能用于 <A HREF="function.mysql-unbuffered-query.html" ><B CLASS="function" >mysql_unbuffered_query()</B ></A >。 </P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN135192" ></A ><H2 >参见</H2 ><P > <P ></P ><TABLE BORDER="0" ><TBODY ><TR ><TD ><A HREF="function.mysql-query.html" ><B CLASS="function" >mysql_query()</B ></A ></TD ></TR ><TR ><TD ><A HREF="function.mysql-num-rows.html" ><B CLASS="function" >mysql_num_rows()</B ></A ></TD ></TR ><TR ><TD ><A HREF="function.mysql-fetch-row.html" ><B CLASS="function" >mysql_fetch_row()</B ></A ></TD ></TR ><TR ><TD ><A HREF="function.mysql-fetch-assoc.html" ><B CLASS="function" >mysql_fetch_assoc()</B ></A ></TD ></TR ><TR ><TD ><A HREF="function.mysql-fetch-array.html" ><B CLASS="function" >mysql_fetch_array()</B ></A ></TD ></TR ><TR ><TD ><A HREF="function.mysql-fetch-object.html" ><B CLASS="function" >mysql_fetch_object()</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.mysql-create-db.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.mysql-db-name.html" ACCESSKEY="N" >下一页</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >mysql_create_db</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.mysql.html" ACCESSKEY="U" >上一级</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >mysql_db_name</TD ></TR ></TABLE ></DIV ></BODY ></HTML >