} arrList.push(new Array(1000000).join('x')) } document.getElementById('btn').addEventListener('click',test) </script> </body> 进入页面,打开performance进行录制,点击三次按钮,停止录制。 可以看到内存是正常的,有升有降,降的地方就是GC在工作了。
Array.push()爆栈 当数组数据量很大时,使用Array.push(...array)的组合还可能出现 JavaScript 堆栈溢出的问题,比如这段代码: 代码语言:ts AI代码解释 const someArray = new Array(600000).fill(1); const newArray = []; let tempArray = []; newArray.push(...someArray); // JS error tempArray ...
performance entry buffer指的是存储performance实例对象的区域,初始值为空。 最后就是given name,表示生成的每一个timestamp都有相应的名称。 所以这句话就可以理解成,在浏览器的performance entry buffer中,根据名称生成高精度时间戳。也就是很多人说过的“打点”。 就像Performance.now一样,此函数的精度分数高达5µ...
2: anonymous (aka anonymous) [0x2480d5c82c81] [/Users/xgqfrms-mbp/Documents/GitHub/AFES/js-basic/array/push-vs-unshift.js:~40] [pc=0x320f7c803a7b](this=0x24805b8004b1 <undefined>,46758526,46758525) 3: map [0x2480d7d95609](this=0x2480d5c82c61 <JSArray[100000000]>,0x2480d5c82c81...
// 创建 heap snapshots let snapshot1 = performance.heapSnapshot(); // 可以是任何可能引起内存泄漏的代码,以下只给出简单的示例 for (let i = 0; i < 100000; i++) { myArray.push({ largeData: new Array(1000000).fill("some data"), id: i }); } // 创建另外一个 snapshot let snap...
// Do some actions that might cause memory leaksfor(leti =0; i <100000; i++) {myArray.push({largeData:newArray(1000000).fill("some data"),id: i});} // Take another heap snapshotletsnapshot2 = performance.heapSnapshot(...
Cycles the carousel to a particular frame (0 based, similar to an array). .carousel('prev') Cycles to the previous item. .carousel('next') Cycles to the next item. Events Bootstrap's carousel class exposes two events for hooking into carousel functionality. Both events have the following ...
functioncreateArray(...elements){lethandler={get(target,propKey,receiver){letindex=Number(propKey);if(index<0){propKey=String(target.length+index);}returnReflect.get(target,propKey,receiver);}};lettarget=[];target.push(...elements);returnnewProxy(target,handler);}复制代码 ...
(3)对象(Object),可通过Object.entries()、Object.keys()和Object.values()方法, 转换为使用上边的数组(Array)的方式进行循环遍历。 3. 测试代码 functiondoObjForLoop1(obj){ letstartTime = performance.now(); for(letkeyinobj){ // console.log(key, obj[key]); ...
In a JavaScript framework some of the performance considerations and potential drawbacks of “Array.unshift()” are as follows. Adding elements to the beginning of an array with unshift() is usually slower than using push() for large JavaScript arrays. This is because unshift() needs to shift...