The best way to split an array into two halves in JavaScript is by using the Array.prototype.slice() method, because it returns a portion of the array without modifying the original array (i.e. in an immutable / non-destructive way). For example: const arr = [1, 2, 3, 4, 5,...
使用Array实例的splice()方法: const list = [1, 2, 3, 4, 5, 6] const half = Math.ceil(list.length / 2); const firstHalf = list.splice(0, half) const secondHalf = list.splice(-half) If the list contains an even number of items, the result is split with exactly half the it...
const fArr = new Array(fillArr.length - 1); const rowSize = fillArr[0].length; const keys = new Array(rowSize); for(let i = 0; i < rowSize; i++) { keys[i] = fillArr[0][i]; } for(let i = 1; i < fillArr.length; i++) { const obj = {}; for(let j = 0; j...
13.编写一个 JavaScript 练习以使用用户定义的名称创建一个变量。 varvar_name = 'abcd'varn = 120;this[var_name] =n; console.log(this[var_name]) 14.编写一个 JavaScript 练习来获取文件名的扩展名. fliename = "system.php"console.log(fliename.split('.').pop()); fliename= "abc.js"; cons...
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{ x = _W + _X } // Update handle element position t.handle.style.left = x - _W_HANDLE_HALF - _X + 'px' _time = ((x - _X) / _W) * t.media.duration // Update currentTime element value t.currentTime.innerHTML = timeFormat( t.media.currentTime, t.options ) if (is...
var dvArray = defaultValue.split(" "); if( dvArray.length > 0 ){ for( var num = 0; num < dvArray.length; num++ ){ this.defaultArray[num] = dvArray[num]; } } } //填充数据并显示picker this.FillData(); //添加click事件 ...
array.splice(start = 0, [delLength = array.length,] [...newItem]) “万能增删”,修改数组,从指定下标元素的前一位开始删除数个元素,然后再插入数个元素,返回被删除的元素的数组; 这是原生 JS 中最强的数组调整函数,可从任意位置一次性删除并插入多个元素; ...
The slice() method is a built-in method provided by JavaScript. This method splits the array into two places. This cut is performed by taking two inputs, the start index and the end index. And based on that, the part will return an array over the indexes. If only the starting index...
functioncountSymbols(string){returnArray.from(string).length;} 或者,使用解构运算符...: 代码语言:javascript 复制 functioncountSymbols(string){return[...string].length;} 使用这些实现,我们现在可以正确地计算码位,这将导致更准确的结果: 代码语言:javascript ...