Javascript web工作人员使用obect URL的生命周期
假设我们启动一个Worker,它从blob创建一个对象URL:Javascript web工作人员使用obect URL的生命周期,javascript,blob,web-worker,Javascript,Blob,Web Worker,假设我们启动一个Worker,它从blob创建一个对象URL: //running in page window var worker = new Worker(workerScriptUrl); //running in worker var u = rootScope.URL || rootScope.webkitURL; var objUrl = u.createObjectURL(blob); …现在(因为我们懒惰),我们从不打电话: u.revokeObjectURL(objUr
//running in page window
var worker = new Worker(workerScriptUrl);
//running in worker
var u = rootScope.URL || rootScope.webkitURL;
var objUrl = u.createObjectURL(blob);
…现在(因为我们懒惰),我们从不打电话:
u.revokeObjectURL(objUrl);
相反,在启动worker的代码中,我们只调用:
worker.terminate();
这会杀死对象url,还是会在原始页面窗口期间保持不变?好的,在没有答案的情况下,我决定自己测试一下:
var u = window.URL || window.webkitURL;
var f='('+
function(rootScope){
var u = rootScope.URL || rootScope.webkitURL;
var blob=new Blob([ "hello world!" ], { type: 'text/plain' } );
var blobURL = u.createObjectURL( blob) ;
rootScope.postMessage(blobURL);
}.toString()+
')(this)';
console.log(f);
// Build a worker from an anonymous function body
var blobURL = u.createObjectURL( new Blob([ f ],
{ type: 'application/javascript' } ) );
var worker = new Worker( blobURL );
worker.onmessage=function(e){
worker.terminate();
setTimeout(function(){
var xhr = new XMLHttpRequest();
xhr.open('GET', e.data, false);
xhr.send(null);
console.log( xhr.responseText ); //prints "hello world!"
},5000);
};
// Won't be needing this anymore
u.revokeObjectURL( blobURL );
可以看出,即使在终止web worker五秒钟后,我们仍然可以读取它创建的对象URL