不同PHP 版本下mysql_field_type 函數的表現差異是什麼？如何適應？

gitbox 2025-06-12

在php中， mysql_field_type（）是用於獲取mysql數據庫結果集的字段類型的函數。它可以幫助開發者了解查詢結果中的每個字段的數據類型。然而，隨著php的版本更新，特別是php 7.x 7 ，mysql_field_type（）已經被標記為廢棄

1。 mysql_field_type （）的基本功能

mysql_field_type（）函數的作用是獲取指定字段的mysql數據類型。這在處理查詢結果時非常有用，尤其是當你需要根據字段類型做不同的處理時。其語法如下：

 <span><span><span class="hljs-keyword">string</span></span><span> </span><span><span class="hljs-title function_ invoke__">mysql_field_type</span></span><span> ( resource </span><span><span class="hljs-variable">$result</span></span><span> , </span><span><span class="hljs-keyword">int</span></span><span> </span><span><span class="hljs-variable">$field_offset</span></span><span> )
</span></span>

$結果：mysql查詢結果集資源。
$ field_offset ：字段的偏移量，從，0開始。

例如，使用mysql_field_type（）獲取字段類型的代碼如下：

 <span><span><span class="hljs-meta">&lt;?php</span></span><span>
</span><span><span class="hljs-variable">$link</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysql_connect</span></span><span>(</span><span><span class="hljs-string">'localhost'</span></span><span>, </span><span><span class="hljs-string">'root'</span></span><span>, </span><span><span class="hljs-string">'password'</span></span><span>);
</span><span><span class="hljs-title function_ invoke__">mysql_select_db</span></span><span>(</span><span><span class="hljs-string">'test'</span></span><span>, </span><span><span class="hljs-variable">$link</span></span><span>);

</span><span><span class="hljs-variable">$query</span></span><span> = </span><span><span class="hljs-string">'SELECT * FROM users'</span></span><span>;
</span><span><span class="hljs-variable">$result</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysql_query</span></span><span>(</span><span><span class="hljs-variable">$query</span></span><span>, </span><span><span class="hljs-variable">$link</span></span><span>);

</span><span><span class="hljs-variable">$field_type</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysql_field_type</span></span><span>(</span><span><span class="hljs-variable">$result</span></span><span>, </span><span><span class="hljs-number">0</span></span><span>);  </span><span><span class="hljs-comment">// &#33719;&#21462;&#31532;&#19968;&#20010;&#23383;&#27573;&#30340;&#31867;&#22411;</span></span><span>
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"Field type: "</span></span><span> . </span><span><span class="hljs-variable">$field_type</span></span><span>;
</span><span><span class="hljs-meta">?&gt;</span></span><span>
</span></span>

2。在php 5.x中的表現

在php 5.x中， mysql_field_type（）函數是可用的

示例（（php 5.x）

 <span><span><span class="hljs-meta">&lt;?php</span></span><span>
</span><span><span class="hljs-variable">$link</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysql_connect</span></span><span>(</span><span><span class="hljs-string">'localhost'</span></span><span>, </span><span><span class="hljs-string">'root'</span></span><span>, </span><span><span class="hljs-string">'password'</span></span><span>);
</span><span><span class="hljs-title function_ invoke__">mysql_select_db</span></span><span>(</span><span><span class="hljs-string">'test'</span></span><span>, </span><span><span class="hljs-variable">$link</span></span><span>);

</span><span><span class="hljs-variable">$query</span></span><span> = </span><span><span class="hljs-string">'SELECT id, name FROM users'</span></span><span>;
</span><span><span class="hljs-variable">$result</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysql_query</span></span><span>(</span><span><span class="hljs-variable">$query</span></span><span>, </span><span><span class="hljs-variable">$link</span></span><span>);

</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">'Field 1 type: '</span></span><span> . </span><span><span class="hljs-title function_ invoke__">mysql_field_type</span></span><span>(</span><span><span class="hljs-variable">$result</span></span><span>, </span><span><span class="hljs-number">0</span></span><span>); </span><span><span class="hljs-comment">// &#36755;&#20986;&#23383;&#27573;&#31867;&#22411;</span></span><span>
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">'Field 2 type: '</span></span><span> . </span><span><span class="hljs-title function_ invoke__">mysql_field_type</span></span><span>(</span><span><span class="hljs-variable">$result</span></span><span>, </span><span><span class="hljs-number">1</span></span><span>); </span><span><span class="hljs-comment">// &#36755;&#20986;&#23383;&#27573;&#31867;&#22411;</span></span><span>
</span><span><span class="hljs-meta">?&gt;</span></span><span>
</span></span>

3。 PHP7.x及之後版本中的變化

從php 7開始， mysql_*系列函數被標記為廢棄，並且在php 7.0中已經完全移除。這意味著mysql_field_type（）函數不再可用。 php7及更高版本推薦使用mysqli pdo pdo來進行數據庫操作，而這些擴展提供了更現代、更加安全和高效的接口。，而這些擴展提供了更現代、更加安全和高效的接口。

使用mysqli替代mysql_field_type（）

在php 7.x及以上版本中，如果你需要獲取字段的類型

<span><span><span class="hljs-meta">&lt;?php</span></span><span>
</span><span><span class="hljs-variable">$link</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysqli_connect</span></span><span>(</span><span><span class="hljs-string">'localhost'</span></span><span>, </span><span><span class="hljs-string">'root'</span></span><span>, </span><span><span class="hljs-string">'password'</span></span><span>, </span><span><span class="hljs-string">'test'</span></span><span>);

</span><span><span class="hljs-variable">$query</span></span><span> = </span><span><span class="hljs-string">'SELECT id, name FROM users'</span></span><span>;
</span><span><span class="hljs-variable">$result</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysqli_query</span></span><span>(</span><span><span class="hljs-variable">$link</span></span><span>, </span><span><span class="hljs-variable">$query</span></span><span>);

</span><span><span class="hljs-variable">$field</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mysqli_fetch_field</span></span><span>(</span><span><span class="hljs-variable">$result</span></span><span>); </span><span><span class="hljs-comment">// &#33719;&#21462;&#23383;&#27573;&#20449;&#24687;</span></span><span>
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">'Field 1 type: '</span></span><span> . </span><span><span class="hljs-variable">$field</span></span><span>-&gt;type;  </span><span><span class="hljs-comment">// &#33719;&#21462;&#23383;&#27573;&#31867;&#22411;</span></span><span>
</span><span><span class="hljs-meta">?&gt;</span></span><span>
</span></span>

在這個示例中， $ field-> type會返回字段的類型，例如mysqli_type_long ， mysqli_type_string等，開發者可以根據這些常量來處理不同類型的字段。，開發者可以根據這些常量來處理不同類型的字段。

使用pDO替代mysql_field_type（）

如果你使用pdo來處理數據庫操作，可以通過pdostatement :: getColumnMeta（）方法獲取字段的類型信息。以下是一個使用pdo的示例::

 <span><span><span class="hljs-meta">&lt;?php</span></span><span>
</span><span><span class="hljs-variable">$dsn</span></span><span> = </span><span><span class="hljs-string">'mysql:host=localhost;dbname=test'</span></span><span>;
</span><span><span class="hljs-variable">$username</span></span><span> = </span><span><span class="hljs-string">'root'</span></span><span>;
</span><span><span class="hljs-variable">$password</span></span><span> = </span><span><span class="hljs-string">'password'</span></span><span>;

</span><span><span class="hljs-keyword">try</span></span><span> {
    </span><span><span class="hljs-variable">$pdo</span></span><span> = </span><span><span class="hljs-keyword">new</span></span><span> </span><span><span class="hljs-title function_ invoke__">PDO</span></span><span>(</span><span><span class="hljs-variable">$dsn</span></span><span>, </span><span><span class="hljs-variable">$username</span></span><span>, </span><span><span class="hljs-variable">$password</span></span><span>);
    </span><span><span class="hljs-variable">$pdo</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">setAttribute</span></span><span>(PDO::</span><span><span class="hljs-variable constant_">ATTR_ERRMODE</span></span><span>, PDO::</span><span><span class="hljs-variable constant_">ERRMODE_EXCEPTION</span></span><span>);

    </span><span><span class="hljs-variable">$stmt</span></span><span> = </span><span><span class="hljs-variable">$pdo</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">query</span></span><span>(</span><span><span class="hljs-string">'SELECT id, name FROM users'</span></span><span>);
    </span><span><span class="hljs-variable">$meta</span></span><span> = </span><span><span class="hljs-variable">$stmt</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getColumnMeta</span></span><span>(</span><span><span class="hljs-number">0</span></span><span>);  </span><span><span class="hljs-comment">// &#33719;&#21462;&#31532;&#19968;&#21015;&#30340;&#20803;&#25968;&#25454;</span></span><span>

    </span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">'Field 1 type: '</span></span><span> . </span><span><span class="hljs-variable">$meta</span></span><span>[</span><span><span class="hljs-string">'native_type'</span></span><span>];  </span><span><span class="hljs-comment">// &#33719;&#21462;&#23383;&#27573;&#31867;&#22411;</span></span><span>
} </span><span><span class="hljs-keyword">catch</span></span><span> (PDOException </span><span><span class="hljs-variable">$e</span></span><span>) {
    </span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">'Connection failed: '</span></span><span> . </span><span><span class="hljs-variable">$e</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getMessage</span></span><span>();
}
</span><span><span class="hljs-meta">?&gt;</span></span><span>
</span></span>

在這個例子中， getColumnMeta（）方法返回的元數據數組包含了字段的原始類型。

4。如何適應這些變化？

為了確保你的代碼兼容現代php 版本（尤其是 php 7及之後的版本），你應該：：

棄用mysql_*函數：不再使用mysql_*函數，因為這些函數已經被廢棄
遷移到mysqli或pdo ：如果你還在使用mysql_*函數
檢查字段類型時使用替代方法：如果你需要獲取字段的類型，使用mysqli的mysqli_fetch_field（）或pdo的getColumnMeta（）來替代mysql_field_type（）。

5

隨著php版本的更新， mysql_field_type（）函數已經不再適用，mysqli pdo（pdo）。雖然在php 5.x 5.x，但在更高版本中，使用，mysqli pdo提供的替代方法