當前位置: 首頁> 最新文章列表> 使用get_meta_tags 獲取頁面標題和關鍵字時的常見問題及解決辦法

使用get_meta_tags 獲取頁面標題和關鍵字時的常見問題及解決辦法

gitbox 2025-09-16

get_meta_tags()是PHP 內置的一個方便函數，用來從遠程或本地HTML 文件中提取<meta name="...">標籤的內容。它常被用於抓取頁面關鍵字（keywords）或描述（description）。然而在實際使用中，開發者會遇到各種問題：提取不到標題、關鍵字為空、字符編碼錯亂、遠程請求失敗、meta 標籤寫法不規範等。本文總結常見問題、產生原因，並給出對策與更健壯的替代方案（含可複制的PHP 示例代碼）。

1. get_meta_tags()的工作方式與限制（先理解再調試）

  • get_meta_tags(string $filename, bool $use_include_path = false) ：它讀取文件並嘗試解析<meta name="xxx" content="yyy"> ，返回一個關聯數組name => content （全部小寫的name）。

  • 它不會獲取<title>標籤內容（即頁面標題），也不會解析<meta property="og:...">或<meta charset="...">等非name屬性的meta。

  • 它對HTML 的要求相對嚴格：meta 必須以name="..."與content="..."的形式存在，屬性順序或換行有時會影響解析。

結論：如果你需要頁面<title> ，或meta用了property （如Open Graph）， get_meta_tags()單獨使用就不夠了。

2. 常見問題與解決辦法一覽

問題A：無法獲取<title> （頁面標題）

原因： get_meta_tags()不解析<title> 。
解決辦法：用DOMDocument或正則（不推薦）解析<title> 。示例（推薦DOMDocument ）：

 <span><span><span class="hljs-function"><span class="hljs-keyword">function</span></span></span><span> </span><span><span class="hljs-title">fetch_title</span></span><span>(</span><span><span class="hljs-params"><span class="hljs-variable">$html</span></span></span><span>) {
    </span><span><span class="hljs-variable">$dom</span></span><span> = </span><span><span class="hljs-keyword">new</span></span><span> </span><span><span class="hljs-title class_">DOMDocument</span></span><span>();
    </span><span><span class="hljs-comment">// suppress warnings for malformed HTML</span></span><span>
    @</span><span><span class="hljs-variable">$dom</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">loadHTML</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>, LIBXML_NOWARNING | LIBXML_NOERROR);
    </span><span><span class="hljs-variable">$nodes</span></span><span> = </span><span><span class="hljs-variable">$dom</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getElementsByTagName</span></span><span>(</span><span><span class="hljs-string">'title'</span></span><span>);
    </span><span><span class="hljs-keyword">return</span></span><span> </span><span><span class="hljs-variable">$nodes</span></span><span>-&gt;length ? </span><span><span class="hljs-title function_ invoke__">trim</span></span><span>(</span><span><span class="hljs-variable">$nodes</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">item</span></span><span>(</span><span><span class="hljs-number">0</span></span><span>)-&gt;textContent) : </span><span><span class="hljs-literal">null</span></span><span>;
}
</span></span>

如果需要遠程獲取頁面內容，請先file_get_contents / curl拉下HTML，再傳給fetch_title() 。

問題B： get_meta_tags()返回空數組或缺失某些meta

可能原因：

  1. HTML meta 的寫法不是name="..." + content="..." （如property="og:..."或http-equiv ）。

  2. meta 在<head>之外（或頁面結構不規範）。

  3. 字符編碼或BOM 導致解析失敗。

  4. allow_url_fopen被禁用，無法使用URL。

解決辦法：

  • 檢查meta 屬性類型，必要時使用DOMDocument檢查meta->getAttribute('name')與meta->getAttribute('property') 。

  • 對遠程URL，優先使用curl獲取頁面內容（更靈活），然後使用DOM 解析。

  • 若allow_url_fopen被禁用，改用curl 。

示例：用curl + DOM 提取常見meta（包括name與property ）與標題：

 <span><span><span class="hljs-function"><span class="hljs-keyword">function</span></span></span><span> </span><span><span class="hljs-title">fetch_html</span></span><span>(</span><span><span class="hljs-params"><span class="hljs-variable">$url</span></span></span><span>, </span><span><span class="hljs-variable">$timeout</span></span><span> = </span><span><span class="hljs-number">10</span></span><span>) {
    </span><span><span class="hljs-variable">$ch</span></span><span> = </span><span><span class="hljs-title function_ invoke__">curl_init</span></span><span>(</span><span><span class="hljs-variable">$url</span></span><span>);
    </span><span><span class="hljs-title function_ invoke__">curl_setopt_array</span></span><span>(</span><span><span class="hljs-variable">$ch</span></span><span>, [
        CURLOPT_RETURNTRANSFER =&gt; </span><span><span class="hljs-literal">true</span></span><span>,
        CURLOPT_FOLLOWLOCATION =&gt; </span><span><span class="hljs-literal">true</span></span><span>,
        CURLOPT_MAXREDIRS =&gt; </span><span><span class="hljs-number">5</span></span><span>,
        CURLOPT_CONNECTTIMEOUT =&gt; </span><span><span class="hljs-variable">$timeout</span></span><span>,
        CURLOPT_TIMEOUT =&gt; </span><span><span class="hljs-variable">$timeout</span></span><span>,
        CURLOPT_USERAGENT =&gt; </span><span><span class="hljs-string">'Mozilla/5.0 (compatible; PHP script)'</span></span><span>,
    ]);
    </span><span><span class="hljs-variable">$html</span></span><span> = </span><span><span class="hljs-title function_ invoke__">curl_exec</span></span><span>(</span><span><span class="hljs-variable">$ch</span></span><span>);
    </span><span><span class="hljs-variable">$err</span></span><span> = </span><span><span class="hljs-title function_ invoke__">curl_error</span></span><span>(</span><span><span class="hljs-variable">$ch</span></span><span>);
    </span><span><span class="hljs-title function_ invoke__">curl_close</span></span><span>(</span><span><span class="hljs-variable">$ch</span></span><span>);
    </span><span><span class="hljs-keyword">if</span></span><span> (</span><span><span class="hljs-variable">$html</span></span><span> === </span><span><span class="hljs-literal">false</span></span><span>) {
        </span><span><span class="hljs-keyword">throw</span></span><span> </span><span><span class="hljs-keyword">new</span></span><span> </span><span><span class="hljs-built_in">RuntimeException</span></span><span>(</span><span><span class="hljs-string">"Failed to fetch URL: <span class="hljs-subst">$err</span></span></span><span>");
    }
    </span><span><span class="hljs-keyword">return</span></span><span> </span><span><span class="hljs-variable">$html</span></span><span>;
}

</span><span><span class="hljs-function"><span class="hljs-keyword">function</span></span></span><span> </span><span><span class="hljs-title">parse_meta_and_title</span></span><span>(</span><span><span class="hljs-params"><span class="hljs-variable">$html</span></span></span><span>) {
    </span><span><span class="hljs-variable">$dom</span></span><span> = </span><span><span class="hljs-keyword">new</span></span><span> </span><span><span class="hljs-title class_">DOMDocument</span></span><span>();
    @</span><span><span class="hljs-variable">$dom</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">loadHTML</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>, LIBXML_NOWARNING | LIBXML_NOERROR);
    </span><span><span class="hljs-variable">$result</span></span><span> = [</span><span><span class="hljs-string">'title'</span></span><span> =&gt; </span><span><span class="hljs-literal">null</span></span><span>, </span><span><span class="hljs-string">'meta'</span></span><span> =&gt; []];

    </span><span><span class="hljs-comment">// title</span></span><span>
    </span><span><span class="hljs-variable">$titles</span></span><span> = </span><span><span class="hljs-variable">$dom</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getElementsByTagName</span></span><span>(</span><span><span class="hljs-string">'title'</span></span><span>);
    </span><span><span class="hljs-keyword">if</span></span><span> (</span><span><span class="hljs-variable">$titles</span></span><span>-&gt;length) {
        </span><span><span class="hljs-variable">$result</span></span><span>[</span><span><span class="hljs-string">'title'</span></span><span>] = </span><span><span class="hljs-title function_ invoke__">trim</span></span><span>(</span><span><span class="hljs-variable">$titles</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">item</span></span><span>(</span><span><span class="hljs-number">0</span></span><span>)-&gt;textContent);
    }

    </span><span><span class="hljs-comment">// metas</span></span><span>
    </span><span><span class="hljs-variable">$metas</span></span><span> = </span><span><span class="hljs-variable">$dom</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getElementsByTagName</span></span><span>(</span><span><span class="hljs-string">'meta'</span></span><span>);
    </span><span><span class="hljs-keyword">foreach</span></span><span> (</span><span><span class="hljs-variable">$metas</span></span><span> </span><span><span class="hljs-keyword">as</span></span><span> </span><span><span class="hljs-variable">$meta</span></span><span>) {
        </span><span><span class="hljs-variable">$name</span></span><span> = </span><span><span class="hljs-variable">$meta</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getAttribute</span></span><span>(</span><span><span class="hljs-string">'name'</span></span><span>);
        </span><span><span class="hljs-variable">$prop</span></span><span> = </span><span><span class="hljs-variable">$meta</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getAttribute</span></span><span>(</span><span><span class="hljs-string">'property'</span></span><span>); </span><span><span class="hljs-comment">// og: 等</span></span><span>
        </span><span><span class="hljs-variable">$http_equiv</span></span><span> = </span><span><span class="hljs-variable">$meta</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getAttribute</span></span><span>(</span><span><span class="hljs-string">'http-equiv'</span></span><span>);
        </span><span><span class="hljs-variable">$content</span></span><span> = </span><span><span class="hljs-variable">$meta</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getAttribute</span></span><span>(</span><span><span class="hljs-string">'content'</span></span><span>);

        </span><span><span class="hljs-keyword">if</span></span><span> (</span><span><span class="hljs-variable">$name</span></span><span>) {
            </span><span><span class="hljs-variable">$result</span></span><span>[</span><span><span class="hljs-string">'meta'</span></span><span>][</span><span><span class="hljs-title function_ invoke__">strtolower</span></span><span>(</span><span><span class="hljs-variable">$name</span></span><span>)] = </span><span><span class="hljs-variable">$content</span></span><span>;
        } </span><span><span class="hljs-keyword">elseif</span></span><span> (</span><span><span class="hljs-variable">$prop</span></span><span>) {
            </span><span><span class="hljs-variable">$result</span></span><span>[</span><span><span class="hljs-string">'meta'</span></span><span>][</span><span><span class="hljs-title function_ invoke__">strtolower</span></span><span>(</span><span><span class="hljs-variable">$prop</span></span><span>)] = </span><span><span class="hljs-variable">$content</span></span><span>;
        } </span><span><span class="hljs-keyword">elseif</span></span><span> (</span><span><span class="hljs-variable">$http_equiv</span></span><span>) {
            </span><span><span class="hljs-variable">$result</span></span><span>[</span><span><span class="hljs-string">'meta'</span></span><span>][</span><span><span class="hljs-title function_ invoke__">strtolower</span></span><span>(</span><span><span class="hljs-variable">$http_equiv</span></span><span>)] = </span><span><span class="hljs-variable">$content</span></span><span>;
        }
    }
    </span><span><span class="hljs-keyword">return</span></span><span> </span><span><span class="hljs-variable">$result</span></span><span>;
}
</span></span>

問題C：字符編碼（中文等多字節）亂碼

原因：

  • 頁面使用的編碼（如UTF-8、GBK）與DOMDocument::loadHTML默認行為不匹配。

  • HTTP header 與頁面meta 中的charset 信息不一致。

解決辦法：

  • 在loadHTML()前把HTML 轉為UTF-8（若不是），並在頭部注入<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> ，這樣DOMDocument更易識別。

  • 使用mb_detect_encoding()判斷編碼並轉換為UTF-8。

示例：

 <span><span><span class="hljs-function"><span class="hljs-keyword">function</span></span></span><span> </span><span><span class="hljs-title">normalize_to_utf8</span></span><span>(</span><span><span class="hljs-params"><span class="hljs-variable">$html</span></span></span><span>) {
    </span><span><span class="hljs-comment">// 嘗試通過 BOM 或 meta 判斷編碼，若不確定則用 mb_detect_encoding</span></span><span>
    </span><span><span class="hljs-variable">$encoding</span></span><span> = </span><span><span class="hljs-literal">null</span></span><span>;
    </span><span><span class="hljs-keyword">if</span></span><span> (</span><span><span class="hljs-title function_ invoke__">preg_match</span></span><span>(</span><span><span class="hljs-string">'/&lt;meta.+?charset=["\']?\s*([a-zA-Z0-9\-\_]+)\b/i'</span></span><span>, </span><span><span class="hljs-variable">$html</span></span><span>, </span><span><span class="hljs-variable">$m</span></span><span>)) {
        </span><span><span class="hljs-variable">$encoding</span></span><span> = </span><span><span class="hljs-title function_ invoke__">strtoupper</span></span><span>(</span><span><span class="hljs-variable">$m</span></span><span>[</span><span><span class="hljs-number">1</span></span><span>]);
    }
    </span><span><span class="hljs-keyword">if</span></span><span> (!</span><span><span class="hljs-variable">$encoding</span></span><span>) {
        </span><span><span class="hljs-variable">$encoding</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mb_detect_encoding</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>, [</span><span><span class="hljs-string">'UTF-8'</span></span><span>,</span><span><span class="hljs-string">'GB2312'</span></span><span>,</span><span><span class="hljs-string">'GBK'</span></span><span>,</span><span><span class="hljs-string">'ISO-8859-1'</span></span><span>], </span><span><span class="hljs-literal">true</span></span><span>);
    }
    </span><span><span class="hljs-keyword">if</span></span><span> (</span><span><span class="hljs-variable">$encoding</span></span><span> &amp;&amp; </span><span><span class="hljs-title function_ invoke__">strtoupper</span></span><span>(</span><span><span class="hljs-variable">$encoding</span></span><span>) !== </span><span><span class="hljs-string">'UTF-8'</span></span><span>) {
        </span><span><span class="hljs-variable">$html</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mb_convert_encoding</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>, </span><span><span class="hljs-string">'UTF-8'</span></span><span>, </span><span><span class="hljs-variable">$encoding</span></span><span>);
    }
    </span><span><span class="hljs-comment">// 保證 loadHTML 識別為 UTF-8</span></span><span>
    </span><span><span class="hljs-keyword">if</span></span><span> (</span><span><span class="hljs-title function_ invoke__">stripos</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>, </span><span><span class="hljs-string">'&lt;meta http-equiv="Content-Type"'</span></span><span>) === </span><span><span class="hljs-literal">false</span></span><span>) {
        </span><span><span class="hljs-variable">$html</span></span><span> = </span><span><span class="hljs-title function_ invoke__">preg_replace</span></span><span>(</span><span><span class="hljs-string">'/&lt;head([^&gt;]*)&gt;/i'</span></span><span>, </span><span><span class="hljs-string">'&lt;head$1&gt;&lt;meta http-equiv="Content-Type" content="text/html; charset=utf-8"&gt;'</span></span><span>, </span><span><span class="hljs-variable">$html</span></span><span>, </span><span><span class="hljs-number">1</span></span><span>);
    }
    </span><span><span class="hljs-keyword">return</span></span><span> </span><span><span class="hljs-variable">$html</span></span><span>;
}
</span></span>

問題D： get_meta_tags()對HTML 註釋或不規則格式敏感

原因：函數內部基於簡單的解析器，遇到換行、註釋、或在content屬性中嵌套奇怪字符會失敗。
解決辦法：使用DOMDocument容錯更好；或者先把HTML 中頭部做預處理（去除註釋、壓平屬性到同一行）再調用get_meta_tags() （不太優雅，但可作為短期補救）。

問題E：抓取遠程頁面超時、被反爬或返回403/429

對策：

  • 使用CURLOPT_USERAGENT設置常見瀏覽器UA。

  • 設置合理的CURLOPT_TIMEOUT與CURLOPT_CONNECTTIMEOUT 。

  • 支持CURLOPT_FOLLOWLOCATION （注意在某些環境中需要啟用）。

  • 若站點有反爬策略（驗證碼、JS 渲染、反機器人），考慮：

    • 簡單請求頭偽裝（但要遵守法律與網站robots 協議）。

    • 使用帶JS 的抓取工具（如headless 瀏覽器），但這超出PHP 原生範疇。

  • 處理HTTP 狀態碼並在失敗時重試（指數回退），但避免過度請求。

示例：帶headers 的curl：

 <span><span><span class="hljs-title function_ invoke__">curl_setopt_array</span></span><span>(</span><span><span class="hljs-variable">$ch</span></span><span>, [
    CURLOPT_RETURNTRANSFER =&gt; </span><span><span class="hljs-literal">true</span></span><span>,
    CURLOPT_FOLLOWLOCATION =&gt; </span><span><span class="hljs-literal">true</span></span><span>,
    CURLOPT_MAXREDIRS =&gt; </span><span><span class="hljs-number">5</span></span><span>,
    CURLOPT_CONNECTTIMEOUT =&gt; </span><span><span class="hljs-number">10</span></span><span>,
    CURLOPT_TIMEOUT =&gt; </span><span><span class="hljs-number">15</span></span><span>,
    CURLOPT_USERAGENT =&gt; </span><span><span class="hljs-string">'Mozilla/5.0 (Windows NT 10.0; Win64; x64)'</span></span><span>,
    CURLOPT_HTTPHEADER =&gt; [
        </span><span><span class="hljs-string">'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8'</span></span><span>,
        </span><span><span class="hljs-string">'Accept-Language: en-US,en;q=0.5'</span></span><span>,
    ],
]);
</span></span>

問題F： get_meta_tags()只返回小寫的鍵名

這是函數的設計：鍵名會被轉為小寫。如果你的業務依賴大小寫敏感的字段，請注意標準化鍵名。

3. 推薦的穩健實現（統一獲取title、keywords、description、og 標籤）

下面給出一個組合函數：先用curl取HTML，再做編碼歸一化，最後用DOM 解析並返回常見字段與所有meta 列表。

 <span><span><span class="hljs-function"><span class="hljs-keyword">function</span></span></span><span> </span><span><span class="hljs-title">fetch_page_info</span></span><span>(</span><span><span class="hljs-params"><span class="hljs-variable">$url</span></span></span><span>) {
    </span><span><span class="hljs-variable">$html</span></span><span> = </span><span><span class="hljs-title function_ invoke__">fetch_html</span></span><span>(</span><span><span class="hljs-variable">$url</span></span><span>);
    </span><span><span class="hljs-variable">$html</span></span><span> = </span><span><span class="hljs-title function_ invoke__">normalize_to_utf8</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>);
    </span><span><span class="hljs-variable">$data</span></span><span> = </span><span><span class="hljs-title function_ invoke__">parse_meta_and_title</span></span><span>(</span><span><span class="hljs-variable">$html</span></span><span>);

    </span><span><span class="hljs-comment">// 常見字段規範化：title, keywords, description</span></span><span>
    </span><span><span class="hljs-variable">$info</span></span><span> = [];
    </span><span><span class="hljs-variable">$info</span></span><span>[</span><span><span class="hljs-string">'title'</span></span><span>] = </span><span><span class="hljs-variable">$data</span></span><span>[</span><span><span class="hljs-string">'title'</span></span><span>] ?? </span><span><span class="hljs-literal">null</span></span><span>;
    </span><span><span class="hljs-variable">$meta</span></span><span> = </span><span><span class="hljs-variable">$data</span></span><span>[</span><span><span class="hljs-string">'meta'</span></span><span>] ?? [];

    </span><span><span class="hljs-variable">$info</span></span><span>[</span><span><span class="hljs-string">'keywords'</span></span><span>] = </span><span><span class="hljs-variable">$meta</span></span><span>[</span><span><span class="hljs-string">'keywords'</span></span><span>] ?? (</span><span><span class="hljs-variable">$meta</span></span><span>[</span><span><span class="hljs-string">'og:site_name'</span></span><span>] ?? </span><span><span class="hljs-literal">null</span></span><span>);
    </span><span><span class="hljs-variable">$info</span></span><span>[</span><span><span class="hljs-string">'description'</span></span><span>] = </span><span><span class="hljs-variable">$meta</span></span><span>[</span><span><span class="hljs-string">'description'</span></span><span>] ?? (</span><span><span class="hljs-variable">$meta</span></span><span>[</span><span><span class="hljs-string">'og:description'</span></span><span>] ?? </span><span><span class="hljs-literal">null</span></span><span>);

    </span><span><span class="hljs-comment">// 返回所有 meta 以便進一步使用</span></span><span>
    </span><span><span class="hljs-variable">$info</span></span><span>[</span><span><span class="hljs-string">'meta_all'</span></span><span>] = </span><span><span class="hljs-variable">$meta</span></span><span>;

    </span><span><span class="hljs-keyword">return</span></span><span> </span><span><span class="hljs-variable">$info</span></span><span>;
}

</span><span><span class="hljs-comment">// 使用例子：</span></span><span>
</span><span><span class="hljs-keyword">try</span></span><span> {
    </span><span><span class="hljs-variable">$url</span></span><span> = </span><span><span class="hljs-string">'https://example.com'</span></span><span>;
    </span><span><span class="hljs-variable">$info</span></span><span> = </span><span><span class="hljs-title function_ invoke__">fetch_page_info</span></span><span>(</span><span><span class="hljs-variable">$url</span></span><span>);
    </span><span><span class="hljs-title function_ invoke__">var_export</span></span><span>(</span><span><span class="hljs-variable">$info</span></span><span>);
} </span><span><span class="hljs-keyword">catch</span></span><span> (</span><span><span class="hljs-built_in">Exception</span></span><span> </span><span><span class="hljs-variable">$e</span></span><span>) {
    </span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"Error: "</span></span><span> . </span><span><span class="hljs-variable">$e</span></span><span>-&gt;</span><span><span class="hljs-title function_ invoke__">getMessage</span></span><span>();
}
</span></span>

4. 性能與緩存建議

  • 若需要批量抓取大量頁面，請不要每次都實時抓取同一URL。建議使用緩存（Redis、Memcached 或文件緩存）並設置合適的過期策略，例如1 小時或24 小時，視頁面更新頻率而定。

  • 並發抓取時控制並發數，避免被目標站點封禁或自己主機壓力過高。

  • 對於大型站點優先抓取首頁& 重要頁面，避免盲目抓取所有鏈接。

5. 補充技巧與註意事項

  • meta tags 寫法不統一：很多現代站點使用og:title 、 twitter:title ，這些都不在get_meta_tags()的目標範圍內，使用DOM 能一次性抓取全部類型。

  • meta 標籤重複：如果頁面中出現多個同名meta（可能用於多語言或版本控制），你的解析邏輯應決定是取第一個、合併還是全部保存。

  • meta 中的HTML 實體：注意對& 、 &#123;等實體進行解碼（ html_entity_decode() ）。

  • robots/meta-refresh ：如果需要處理meta refresh（重定向）或robots noindex，請專門檢查http-equiv和相應屬性。

  • 遵守robots.txt 與法律：抓取前請檢查目標站點robots.txt 與服務條款，尊重隱私與版權，不要抓取受限制內容。

6. 實用checklist（快速排查步驟）

  1. 確認你要抓取的是<meta name="keywords">還是<title> （兩者不同工具）。

  2. 如果是遠程抓取：先用curl獲取並打印原始HTML，查看meta 的具體寫法與編碼。

  3. 檢查charset ，若非UTF-8，先轉換再解析。

  4. 若get_meta_tags()無法提取，切換到DOMDocument ，並同時捕獲name 、 property與http-equiv 。

  5. 處理HTTP 錯誤、重定向與反爬機制（適當設置UA、超時與重試策略）。

  6. 對重要頁面實現緩存，避免重複請求。

7. 總結

  • get_meta_tags()簡單易用，但只適用於標準且簡單的meta name="..."場景。它不會抓取<title>或property類型的meta。

  • 面對複雜、非標准或非UTF-8 的頁面，推薦使用curl + DOMDocument的組合：更靈活、魯棒性更高。

  • 編碼、遠程請求失敗、反爬、meta 寫法不規範是常見故障點，按照上文的排查順序即可定位並修復大部分問題。

  • 若需處理需要JS 渲染的頁面（SPA、動態加載meta），則需要使用headless 瀏覽器或服務器端渲染的方案（超出PHP 原生範圍）。

相關內容
最新文章