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diff --git a/files/zh-cn/web/guide/api/camera/index.html b/files/zh-cn/web/guide/api/camera/index.html deleted file mode 100644 index 64fe08d634..0000000000 --- a/files/zh-cn/web/guide/api/camera/index.html +++ /dev/null @@ -1,219 +0,0 @@ ---- -title: 使用Camera API -slug: Web/Guide/API/Camera -translation_of: Archive/B2G_OS/API/Camera_API/Introduction ---- -<p>通过<a class="link-https" href="https://wiki.mozilla.org/Platform/Features/Camera_API">Camera API</a>,你可以使用手机的摄像头拍照,然后把拍到的照片发送给当前网页.这些操作主要是通过一个<code>input元素</code>来实现的,其中该元素的<code>type属性必须为"file",</code><code>accept属性要允许图片格式,</code>这样才能知道这个文件选择框是用来选择图片的.,完整的HTML结构看起来是这样的:</p> -<pre class="brush: html"><input type="file" id="take-picture" accept="image/*"> -</pre> -<p>当用户激活这个HTML元素的时候,系统会呈现给用户一个选择界面,其中一个选项是选择本地的图片文件,另一个选项是要通过摄像头直接 拍摄照片作为所选文件.如果用户选择了摄像头,则会进入手机的拍照模式.拍照结束后,,用户可以选择确定还是放弃.如果接受了,则该照片会作为所选文件发 送给那个<code><input type="file"></code>元素,同时触发该元素的<code>onchange事件</code>.</p> -<h2 id="获取到所拍摄照片的引用">获取到所拍摄照片的引用</h2> -<p>通过<a href="/en/Using_files_from_web_applications" title="en/Using_files_from_web_applications">File API</a>,你可以获取到用户所拍摄的照片或者所选择的图片文件的引用:</p> -<pre class="brush: js">var takePicture = document.querySelector("#take-picture"); -takePicture.onchange = function (event) { - // 获得图片文件的引用 - var files = event.target.files, - file; - if (files && files.length > 0) { - file = files[0]; - } -}; -</pre> -<h2 id="在网页中展示图片">在网页中展示图片</h2> -<p>如果你获取到了那张照片的引用(也就是File对象),你就可以使用{{ domxref("window.URL.createObjectURL()") }}方法创建一个指向那个照片的URL,然后把得到的URL赋给<code>img</code>元素的<code>src属性</code>:</p> -<pre class="brush: js">// 获取到img元素 -var showPicture = document.querySelector("#show-picture"); - -// 获取到window.URL对象 -var URL = window.URL || window.webkitURL; - -// 创建一个对象URL字符串 -var imgURL = URL.createObjectURL(file); - -// 设置img元素的src属性为那个URL -showPicture.src = imgURL; - -// 释放那个对象URL,提高性能 -URL.revokeObjectURL(imgURL); -</pre> -<p>如果浏览器不支持<code>createObjectURL()</code>方法,还可以使用{{ domxref("FileReader") }}来实现:</p> -<pre class="brush: js">// 如果createObjectURL方法不可用 -var fileReader = new FileReader(); -fileReader.onload = function (event) { - showPicture.src = event.target.result; -}; -fileReader.readAsDataURL(file); -</pre> -<h2 id="完整的示例代码">完整的示例代码</h2> -<p>这里有一个<a class="external" href="http://robnyman.github.com/camera-api/">完整的使用Camera API的demo</a>,下面是这个demo的完整代码:</p> -<h3 id="HTML页面">HTML页面:</h3> -<pre class="brush: html"><!DOCTYPE html> -<html> - <head> - <meta charset="utf-8"> - <title>Camera API</title> - <link rel="stylesheet" href="css/base.css" type="text/css" media="screen"> - </head> - - <body> - - <div class="container"> - <h1>Camera API</h1> - - <section class="main-content"> - <p>A demo of the Camera API, currently implemented in Firefox and Google Chrome on Android. Choose to take a picture with your device's camera and a preview will be shown through createObjectURL or a FileReader object (choosing local files supported too).</p> - - <p> - <input type="file" id="take-picture" accept="image/*"> - </p> - - <h2>Preview:</h2> - <p> - <img src="about:blank" alt="" id="show-picture"> - </p> - - <p id="error"></p> - - </section> - - <p class="footer">All the code is available in the <a href="https://github.com/robnyman/robnyman.github.com/tree/master/camera-api">Camera API repository on GitHub</a>.</p> - </div> - - - <script src="js/base.js"></script> - - - </body> -</html> -</pre> -<h3 id="JavaScript文件">JavaScript文件:</h3> -<pre class="brush: js">(function () { - var takePicture = document.querySelector("#take-picture"), - showPicture = document.querySelector("#show-picture"); - - if (takePicture && showPicture) { - // Set events - takePicture.onchange = function (event) { - // Get a reference to the taken picture or chosen file - var files = event.target.files, - file; - if (files && files.length > 0) { - file = files[0]; - try { - // Get window.URL object - var URL = window.URL || window.webkitURL; - - // Create ObjectURL - var imgURL = URL.createObjectURL(file); - - // Set img src to ObjectURL - showPicture.src = imgURL; - - // Revoke ObjectURL - URL.revokeObjectURL(imgURL); - } - catch (e) { - try { - // Fallback if createObjectURL is not supported - var fileReader = new FileReader(); - fileReader.onload = function (event) { - showPicture.src = event.target.result; - }; - fileReader.readAsDataURL(file); - } - catch (e) { - // - var error = document.querySelector("#error"); - if (error) { - error.innerHTML = "Neither createObjectURL or FileReader are supported"; - } - } - } - } - }; - } -})(); -</pre> -<h2 id="浏览器兼容性">浏览器兼容性</h2> -<p>{{ CompatibilityTable() }}</p> -<div id="compat-desktop"> - <table class="compat-table"> - <tbody> - <tr> - <th>Feature</th> - <th>Chrome</th> - <th>Firefox (Gecko)</th> - <th>Internet Explorer</th> - <th>Opera</th> - <th>Safari</th> - </tr> - <tr> - <td>Camera API</td> - <td>{{ CompatNo() }}</td> - <td>{{ CompatNo() }}</td> - <td>{{ CompatNo() }}</td> - <td>{{ CompatNo() }}</td> - <td>{{ CompatNo() }}</td> - </tr> - <tr> - <td><code><a href="/en-US/docs/DOM/window.URL.createObjectURL" title="/en-US/docs/DOM/window.URL.createObjectURL">createObjectURL()</a></code></td> - <td>16</td> - <td>{{CompatGeckoDesktop("8.0")}}</td> - <td>10+</td> - <td>{{CompatNo()}}</td> - <td>{{CompatNo()}}</td> - </tr> - <tr> - <td>{{domxref("FileReader")}}</td> - <td>16</td> - <td>{{CompatGeckoDesktop("1.9.2")}}</td> - <td>10+</td> - <td>11.6+</td> - <td>{{CompatNo()}}</td> - </tr> - </tbody> - </table> -</div> -<div id="compat-mobile"> - <table class="compat-table"> - <tbody> - <tr> - <th>Feature</th> - <th>Android</th> - <th>Chrome for Android</th> - <th>Firefox Mobile (Gecko)</th> - <th>IE Mobile</th> - <th>Opera Mobile</th> - <th>Safari Mobile</th> - </tr> - <tr> - <td>Camera API</td> - <td>3.0</td> - <td>{{ CompatVersionUnknown() }}</td> - <td>{{ CompatGeckoMobile("10.0") }}</td> - <td>{{ CompatNo() }}</td> - <td>{{ CompatNo() }}</td> - <td>{{ CompatNo() }}</td> - </tr> - <tr> - <td><code><a href="/en-US/docs/DOM/window.URL.createObjectURL" title="/en-US/docs/DOM/window.URL.createObjectURL">createObjectURL()</a></code></td> - <td>4</td> - <td>{{CompatVersionUnknown()}}</td> - <td>{{CompatGeckoMobile("10.0")}}</td> - <td>{{CompatNo()}}</td> - <td>{{CompatNo()}}</td> - <td>{{CompatNo()}}</td> - </tr> - <tr> - <td>{{domxref("FileReader")}}</td> - <td>3</td> - <td>{{CompatVersionUnknown()}}</td> - <td>{{CompatGeckoMobile("10.0")}}</td> - <td>{{CompatNo()}}</td> - <td>11.1</td> - <td>{{CompatNo()}}</td> - </tr> - </tbody> - </table> -</div> -<p> </p> |