如何使用web worker加载图像?

Dev*_*esk 8 html javascript image web-worker

我正在尝试使用webworker api加载图像.我的html页面中有大图像,需要5分钟来加载所有图像,因此我使用webworker来加载图像.

这是技术..

  1. 我在html页面中保持所有img标签的src属性为空.

  2. 所有图片必须为每个IMG比如:id =唯一的ID events_all_1_01意味着图像src是"图片/关键字/ 事件/全部/ 1/01.JPG ".即最后一部分事件/全部/ 1/01.jpg是id.

Main.html文件

 <body>  
    <script src="js/modernizr.custom.js"></script>
    <script language="javascript">
       window.onload = function(){   
        if (Modernizr.webworkers) {               
            var worker = new Worker('js/webworker/test_ww_23_04.js');  
            worker.onmessage = function(event) {
                var url = event.data.replace(/_/g, "/");
                var image_src = "pictures/keywords/"+url+".jpg";
                var img = new Image();
                img.src = image_src;     
                img.onload = function(){
                    // do stuff when your image is loaded
                    document.getElementById(event.data).src = image_src;
                }                          
            };

            worker.onerror = function(e) {
                alert('Error: Line ' + e.lineno + ' in ' + e.filename + ': ' + e.message);
            };

                var img_container = document.getElementById("wrapper");
                var image_array = img_container.getElementsByTagName('img');
                for(var i=0;i<image_array.length;i++){
                    var img_id = image_array[i].id;
                    console.log(img_id);  // http://jsfiddle.net/5vyseob7/
                    postMessage(img_id); // http://jsfiddle.net/k04t6760/ here i am passing id one by one to webworker..
                }
            } // end of if condition                                             
        } // end of window.onload()

    </script>  
    <div id="wrapper" style="height: 500px;width: 200px;overflow-y: auto;border: 1px solid gray;">
        <div id="pictures1">
            <div class="effect-1">
                <div><img src="" id="events_all_1_01" width="150" height="100"></div>
                <div><img src="" id="events_all_1_02" width="150" height="100"></div>
                <div><img src="" id="events_all_1_03" width="150" height="100"></div>
                <div><img src="" id="events_all_1_04" width="150" height="100"></div>
            </div>
            <hr/>
            <div class="effect-2">
                <div><img src="" id="events_all_2_01" width="150" height="100"></div>
                <div><img src="" id="events_all_2_02" width="150" height="100"></div>
                <div><img src="" id="events_all_2_03" width="150" height="100"></div>
                <div><img src="" id="events_all_2_04" width="150" height="100"></div>
            </div>
            <hr/>
            <div class="effect-3">
                <div><img src="" id="events_all_3_01" width="150" height="100"></div>
                <div><img src="" id="events_all_3_02" width="150" height="100"></div>
                <div><img src="" id="events_all_3_03" width="150" height="100"></div>
                <div><img src="" id="events_all_3_04" width="150" height="100"></div>
            </div>
            <hr/>
            <div class="effect-4">
                <div><img src="" id="events_all_4_01" width="150" height="100"></div>
                <div><img src="" id="events_all_4_02" width="150" height="100"></div>
                <div><img src="" id="events_all_4_03" width="150" height="100"></div>
                <div><img src="" id="events_all_4_04" width="150" height="100"></div>
            </div>
        </div>
    </div>
</body> 
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网络工程师代码.

 //var src = 'pictures/keywords/events/all/1/01.jpg';
 //var id = src.substring(src.substring(0,18).length).split('.')[0].replace(/\//g, "_"); // Creating id here......events_all_1_01
 //var fst = id.substring(0, id.lastIndexOf("_")+1); // get first part.... events_all_1
 //var lst = parseInt(id.substr(id.lastIndexOf("_")+1)); // get last part i.e imagename ..01,02,03 etc....... and convert it to int

    function LoadImages(currID) {
            setTimeout(function() {
                postMessage(currID); 
            }, 100);  
    }
    self.onmessage = function(event) {
        var currID = event.data;
        LoadImages(currID); 
    };
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我收到以下错误:

未捕获的SyntaxError:无法在'Window'上执行'postMessage':在'postMessage'调用中无效的目标原点''.

raf*_*uto 3

打字错误:

...
worker.onmessage = function(event) {
  var url = e.data.replace(/_/g, "/");
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e未定义...您可能是指function(e)event.data.replace

更新

Window没有postMessage方法...你需要使用worker方法worker.postMessage