Laravel 請求：判斷是否是 Ajax 請求

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                        <ul id="tocify-header0" class="tocify-header nav nav-list"><li class="tocify-item active" data-unique="5dc99f"><a>問題</a></li></ul><ul id="tocify-header1" class="tocify-header nav nav-list"><li class="tocify-item" data-unique="29f56d"><a>方法一、ajax () 函數</a></li><ul class="tocify-subheader nav nav-list" data-tag="3"><li class="tocify-item" data-unique="165dcc"><a>直接訪問的話：</a></li><li class="tocify-item" data-unique="43ddcd"><a>使用 Ajax 訪問：</a></li></ul></ul><ul id="tocify-header2" class="tocify-header nav nav-list"><li class="tocify-item" data-unique="f8ed16"><a>方法二、expectsJson ()</a></li></ul></div></div><div name="5dc99f" data-unique="5dc99f"></div><h2 id="5dc99f">問題<a href="#5dc99f" class="anchorific" style="display: none;">#</a></h2>

如何判斷請求是來自 Ajax 或者是正常的 URL 訪問？

方法一、ajax() 函數#

routes/web.php

.
.
.
Route::get('test-ajax', function () {
<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">request</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">-</span><span class="token operator">&gt;</span><span class="token function">ajax</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token single-quoted-string string">'來自 AJAX 請求'</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token single-quoted-string string">'正常訪問'</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>

});

直接訪問的話：#

使用 Ajax 訪問：#

此刻打開 Chrome 控制台，貼入以下內容：

$.get("http://homestead.test/test-ajax", function(data) {
    console.log(data);
});

注意：記得把 homestead.test 換為你自己的域名。

方法二、expectsJson()#

Route::get('test-ajax', function () {
<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">request</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">-</span><span class="token operator">&gt;</span><span class="token function">expectsJson</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token single-quoted-string string">'來自 AJAX 請求'</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token single-quoted-string string">'正常訪問'</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>

});

expectsJson() 使用方法與 ajax() 相近，不過查看源代碼后還是能看到區別：

// 判斷客戶端是否期待返回 JSON 數據
public function expectsJson()
{
    return ($this->ajax() && ! $this->pjax()) || $this->wantsJson();
}
// 判斷客戶端是否「請求返回 JSON 格式」的數據
 public function wantsJson()
 {
 $acceptable = $this->getAcceptableContentTypes();
<span class="token keyword">return</span> <span class="token keyword">isset</span><span class="token punctuation">(</span><span class="token variable">$acceptable</span><span class="token punctuation">[</span><span class="token number">0</span><span class="token punctuation">]</span><span class="token punctuation">)</span> <span class="token operator">&amp;&amp;</span> <span class="token scope">Str<span class="token punctuation">::</span></span><span class="token function">contains</span><span class="token punctuation">(</span><span class="token variable">$acceptable</span><span class="token punctuation">[</span><span class="token number">0</span><span class="token punctuation">]</span><span class="token punctuation">,</span> <span class="token punctuation">[</span><span class="token single-quoted-string string">'/json'</span><span class="token punctuation">,</span> <span class="token single-quoted-string string">'+json'</span><span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

}
// 判斷客服端是否使用 Pjax
 public function pjax()
 {
 return $this->headers->get('X-PJAX') == true;
 }
// 判斷是否 Ajax 請求
 public function ajax()
 {
 return $this->isXmlHttpRequest();
 }
// 判斷 Header 信息里 X-Requested-With 存在，並等於 XMLHttpRequest
 public function isXmlHttpRequest()
 {
 return 'XMLHttpRequest' == $this->headers->get('X-Requested-With');
 }

需要注意的是 ajax() 是判斷 X-Requested-With 標頭，而 wantsJson() 是判斷 Accept 標頭里是否存在 json，而 expectsJson() 是兩種情況去除掉 Pjax 請求。

原文：https://learnku.com/laravel/wikis/25590