快速掌握PHP获取字段数据类型技巧
对于一个初学者来说,他们在学习的过程中肯定要学到灵活的运用各种
mysql_field_type()函数可获得字段的数据类型,该函数的语法格式如下。
string mysql_field_type ( resource $result, int $field_offset )
mysql_field_type()函数类似于函数mysql_field_name(),不过mysql_field_type()函数返回的是字段的数据类型。它的参数的描述如下。
l result:mysql_query()函数执行后返回的结果集。
l field_offset:字段的偏移量,起始值为零。
使用mysql_field_type()函数的示例代码如下:
代码23-12 光盘codes第23章23.3mysql_field_type.php
<ol class="dp-xml"> <li class="alt"><span><span class="tag"><span> ?php </span></span></span></li> <li> <span>$</span><span class="attribute">connection</span><span>=</span><span class="attribute-value">mysql_connect</span><span>("localhost",<br>"root","root") or die("连接服务器失败"); </span> </li> <li class="alt"><span>mysql_select_db("sunyang",$connection) <br>or die("选择数据库失败"); </span></li> <li> <span>$</span><span class="attribute">query</span><span>=</span><span class="attribute-value">"select * from employee"</span><span>; </span> </li> <li class="alt"> <span>$</span><span class="attribute">result</span><span>=</span><span class="attribute-value">mysql_query</span><span>($query) or die<br>("查询数据失败"); </span> </li> <li><span>//执行查询 </span></li> <li class="alt"><span>echo mysql_field_type($result,0); </span></li> <li><span>//第一个字段的数据类型 </span></li> <li class="alt"> <span>echo "</span><span class="tag"><span> </span><span class="tag-name">br</span><span class="tag">></span><span>"; </span></span> </li> <li><span>echo mysql_field_type($result,1); </span></li> <li class="alt"><span>//第二个字段的数据类型 </span></li> <li> <span>echo "</span><span class="tag"><span> </span><span class="tag-name">br</span><span class="tag">></span><span>"; </span></span> </li> <li class="alt"><span>echo mysql_field_type($result,2); </span></li> <li><span>//第三个字段的数据类型 </span></li> <li class="alt"><span>mysql_free_result($result); </span></li> <li><span>mysql_close(); </span></li> <li class="alt"> <span class="tag">?></span><span> </span> </li> </ol>
上面代码执行后将把表employee中的前3个字段的数据类型输出。

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