function.maxdb-fetch-field.html
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Returns the next field in the result set</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.maxdb-fetch-field-direct.html">maxdb_fetch_field_direct</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.maxdb-fetch-fields.html">maxdb_fetch_fields</a></div> <div class="up"><a href="ref.maxdb.html">MaxDB Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.maxdb-fetch-field" class="refentry"> <div class="refnamediv"> <h1 class="refname">maxdb_fetch_field</h1> <h1 class="refname">result->fetch_field</h1> <p class="verinfo">(PECL maxdb:1.0-7.6.00.38)</p><p class="refpurpose"><span class="refname">maxdb_fetch_field</span> -- <span class="refname">result->fetch_field</span> — <span class="dc-title">Returns the next field in the result set</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <p class="para">Procedural style:</p> <div class="methodsynopsis dc-description"> <span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <span class="methodname"><b><b>maxdb_fetch_field</b></b></span> ( <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$result</tt></span> )</div> <p class="para rdfs-comment">Object oriented style (method):</p> <div class="classsynopsis"> <div class="ooclass"><b class="classname">result</b></div> <div class="methodsynopsis dc-description"> <span class="type">mixed</span> <span class="methodname"><b><b>fetch_field</b></b></span> ( <span class="methodparam">void</span> )</div> </div> <p class="para"> The <b>maxdb_fetch_field()</b> returns the definition of one column of a result set as an resource. Call this function repeatedly to retrieve information about all columns in the result set. <b>maxdb_fetch_field()</b> returns <b><tt>FALSE</tt></b> when no more fields are left. </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns an resource which contains field definition informations or <b><tt>FALSE</tt></b> if no field information is available. </p> <p class="para"> <table border="5"> <caption><b>Object properties</b></caption> <colgroup> <thead valign="middle"> <tr valign="middle"> <th colspan="1">Property</th> <th colspan="1">Description</th> </tr> </thead> <tbody valign="middle" class="tbody"> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">name</td> <td colspan="1" rowspan="1" align="left">The name of the column</td> </tr> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">max_length</td> <td colspan="1" rowspan="1" align="left">The maximum width of the field for the result set.</td> </tr> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">type</td> <td colspan="1" rowspan="1" align="left">The data type used for this field</td> </tr> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">decimals</td> <td colspan="1" rowspan="1" align="left">The number of decimals used (for integer fields)</td> </tr> </tbody> </colgroup> </table> </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <div class="example"> <p><b>Example #1 Object oriented style</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$maxdb </span><span style="color: #007700">= new </span><span style="color: #0000BB">maxdb</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">, </span><span style="color: #DD0000">"MONA"</span><span style="color: #007700">, </span><span style="color: #DD0000">"RED"</span><span style="color: #007700">, </span><span style="color: #DD0000">"DEMODB"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/* check connection */<br /></span><span style="color: #007700">if (</span><span style="color: #0000BB">maxdb_connect_errno</span><span style="color: #007700">()) {<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Connect failed: %s\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">maxdb_connect_error</span><span style="color: #007700">());<br /> exit();<br />}<br /><br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">= </span><span style="color: #DD0000">"SELECT name, cno from hotel.customer ORDER BY cno"</span><span style="color: #007700">;<br /><br />if (</span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">query</span><span style="color: #007700">(</span><span style="color: #0000BB">$query</span><span style="color: #007700">)) {<br /><br /> </span><span style="color: #FF8000">/* Get field information for all columns */<br /> </span><span style="color: #007700">while (</span><span style="color: #0000BB">$finfo </span><span style="color: #007700">= </span><span style="color: #0000BB">$result</span><span style="color: #007700">-></span><span style="color: #0000BB">fetch_field</span><span style="color: #007700">()) {<br /><br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Name: %s\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">name</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Table: %s\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">table</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"max. Len: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">max_length</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Flags: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">flags</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Type: %d\n\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">type</span><span style="color: #007700">);<br /> }<br /> </span><span style="color: #0000BB">$result</span><span style="color: #007700">-></span><span style="color: #0000BB">close</span><span style="color: #007700">();<br />}<br /><br /></span><span style="color: #FF8000">/* close connection */<br /></span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">close</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> <div class="example"> <p><b>Example #2 Procedural style</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$link </span><span style="color: #007700">= </span><span style="color: #0000BB">maxdb_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">, </span><span style="color: #DD0000">"MONA"</span><span style="color: #007700">, </span><span style="color: #DD0000">"RED"</span><span style="color: #007700">, </span><span style="color: #DD0000">"DEMODB"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">/* check connection */<br /></span><span style="color: #007700">if (</span><span style="color: #0000BB">maxdb_connect_errno</span><span style="color: #007700">()) {<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Connect failed: %s\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">maxdb_connect_error</span><span style="color: #007700">());<br /> exit();<br />}<br /><br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">= </span><span style="color: #DD0000">"SELECT name, cno from hotel.customer ORDER BY cno"</span><span style="color: #007700">;<br /><br />if (</span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">maxdb_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">, </span><span style="color: #0000BB">$query</span><span style="color: #007700">)) {<br /><br /> </span><span style="color: #FF8000">/* Get field information for all fields */<br /> </span><span style="color: #007700">while (</span><span style="color: #0000BB">$finfo </span><span style="color: #007700">= </span><span style="color: #0000BB">maxdb_fetch_field</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">)) {<br /><br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Name: %s\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">name</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Table: %s\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">table</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"max. Len: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">max_length</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Flags: %d\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">flags</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">printf</span><span style="color: #007700">(</span><span style="color: #DD0000">"Type: %d\n\n"</span><span style="color: #007700">, </span><span style="color: #0000BB">$finfo</span><span style="color: #007700">-></span><span style="color: #0000BB">type</span><span style="color: #007700">);<br /> }<br /> </span><span style="color: #0000BB">maxdb_free_result</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">);<br />}<br /><br /></span><span style="color: #FF8000">/* close connection */<br /></span><span style="color: #0000BB">maxdb_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> <p class="para">The above example will output something similar to:</p> <div class="example-contents"><pre><div class="cdata"><pre>Name: NAMETable:max. Len: 10Flags: -1Type: 2Name: CNOTable:max. Len: 4Flags: -1Type: 0</pre></div> </pre></div> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.maxdb-num-fields.html" class="function" rel="rdfs-seeAlso">maxdb_num_fields()</a></li> <li class="member"><a href="function.maxdb-fetch-field-direct.html" class="function" rel="rdfs-seeAlso">maxdb_fetch_field_direct()</a></li> <li class="member"><a href="function.maxdb-fetch-fields.html" class="function" rel="rdfs-seeAlso">maxdb_fetch_fields()</a></li> <li class="member"><a href="function.maxdb-field-seek.html" class="function" rel="rdfs-seeAlso">maxdb_field_seek()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.maxdb-fetch-field-direct.html">maxdb_fetch_field_direct</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.maxdb-fetch-fields.html">maxdb_fetch_fields</a></div> <div class="up"><a href="ref.maxdb.html">MaxDB Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div></body></html>⌨️ 快捷键说明
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