利用Chrome的后台网络,分析了通过JQuery的$.ajax()把 json 数据 post 给 PHP时的几种情况:
<ul> <li> <p><span><strong>无法</strong></span>在PHP中通过$_POST 以及 $_REQUEST 获取json数据,即</p> <pre class="code"><span>$json</span> = <span>$_POST</span>['json']; <span>//</span><span> empty($json) 为1</span>
注:PHP 默认只识别 application/x-www.form-urlencoded 标准的数据类型,因此,对型如 text/xml 或者 soap 或者 application/octet-stream 之类的内容无法解析,如果用 $_POST 数组来接收就会失败。
<p>js里<span><strong>没有</strong></span>加入属性contentType: "application/json; charset=utf-8",</p> <pre class="code"><span>var</span> submit_sync = <span>function</span><span>() { $.ajax({ type: </span>"post"<span>, url: </span>'add-post-json.php'<span>, async: </span><span>false</span>, <span>//</span><span> 使用同步方式</span> <span>//</span><span> 1 需要使用JSON.stringify 否则格式为 a=2&b=3&now=14...</span> <span>//</span><span> 2 需要强制类型转换,否则格式为 {"a":"2","b":"3"}</span> <span> data: JSON.stringify({ a: parseInt($(</span>'input[name="a"]'<span>).val()), b: parseInt($(</span>'input[name="b"]'<span>).val()), now: </span><span>new</span> Date().getTime() <span>//</span><span> 注意不要在此行增加逗号</span> <span> }), dataType: </span>"json"<span>, success: </span><span>function</span><span>(data) { $(</span>'#result'<span>).text(data.result); } </span><span>//</span><span> 注意不要在此行增加逗号</span> <span> }); }</span>
<span>$json</span> = <span>$GLOBALS</span>['HTTP_RAW_POST_DATA']; <span>//</span><span> empty($json) 为 1</span>
<span>$json</span> = <span>file_get_contents</span>("php://input"); <span>//</span><span> empty($json) 为 0</span>
<p>js里加入属性contentType: "application/json; charset=utf-8",</p> <pre class="code"><span>var</span> submit_sync = <span>function</span><span>() { $.ajax({ type: </span>"post"<span>, url: </span>'add-post-json.php'<span>, async: </span><span>false</span>, <span>//</span><span> 使用同步方式</span> <span>//</span><span> 1 需要使用JSON.stringify 否则格式为 a=2&b=3&now=14...</span> <span>//</span><span> 2 需要强制类型转换,否则格式为 {"a":"2","b":"3"}</span> <span> data: JSON.stringify({ a: parseInt($(</span>'input[name="a"]'<span>).val()), b: parseInt($(</span>'input[name="b"]'<span>).val()), now: </span><span>new</span> Date().getTime() <span>//</span><span> 注意不要在此行增加逗号</span> <span> }), <span><strong>contentType: </strong></span></span><strong>"application/json; charset=utf-8"</strong><span><span><strong>,</strong></span></span>
<em id="__mceDel"><span> dataType: </span>"json"<span>, success: </span><span>function</span><span>(data) { $(</span>'#result'<span>).text(data.result); } </span><span>//</span><span> 注意不要在此行增加逗号</span> <span> }); }</span></em>
<span>$json</span> = <span>$GLOBALS</span>['HTTP_RAW_POST_DATA']; <span>//</span><span> empty($json) 为 0</span>
<span>$json</span> = <span>file_get_contents</span>("php://input"); <span>//</span><span> empty($json) 为 0</span>
<p>是否加入以下</p> <pre class="code"><span>header</span>('Content-Type:application/json;charset=utf-8');
对情况A与情况B的结果没有任何影响。
从5.2版本开始,PHP原生提供json_encode()和json_decode()函数,前者用于编码,后者用于解码。下面这篇博客写的很详细,mark!