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快速掌握PHP获取字段数据类型技巧

Jun 13, 2016 am 11:11 AM
php beginner exist Field study fast Skill master data of type Obtain process

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>
Copy after login

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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