array.indexOf(searchElement[, fromIndex]); const beasts = ['ant', 'bison', 'camel', 'duck', 'bison']; console.log(beasts.indexOf('bison')); // expected output: 1 // start from index 2 console.log(beasts.indexOf('bison', 2)); // expected output: 4 console.log(beasts.indexOf...
startIndex超出了array的有效索引范围。 RankException array是多维的。 示例 该示例调用 方法的IndexOf以下三个重载,以查找字符串数组中字符串的索引: IndexOf(Array, Object),确定字符串数组中字符串“the”的第一个匹配项。 IndexOf(Array, Object, Int32),用于确定字符串数组的第四个元素到最后一个元素中的字...
7,Array.prototype.indexOf() indexOf()方法返回数组中第一次出现给定元素的下标,如果不存在则返回 -1。 constbeasts=['ant','bison','camel','duck','bison'];console.log(beasts.indexOf('bison'));// Expected output: 1// Start from index 2console.log(beasts.indexOf('bison',2));// Expected...
array_slice(array, start, length) -> array subsets array starting from index start (or starting from the end if start is negative) with a length of length. array_element_at(array<E>, index) -> E returns element of array at given index. If index < 0, element_at accesses elements fro...
The value of this parameter is the index at which Simple Log Service starts to extract elements. If the value of the start parameter is a negative number, Simple Log Service starts to extract elements from the end of the array. If the value of the start parameter is a positive number...
用法:array.find(function(currentValue, [index], [arr]),[thisValue]) vararr = [1,2,3,4,5];vararr1 = arr.find(function(value){returnvalue >= 3; }); console.log(arr1);//3 6、findIndex() 方法:返回符合条件(函数内判断)的数组第一个元素位置。
Uint8Array.prototype.fill( value[, start[, end]] ) Fills an array from astartindex to anendindex (non-inclusive) with a providedvalue. vararr=newUint8Array(2);// Set all array elements to the same value:arr.fill(2);varv=arr[0];// returns 2v=arr[1];// returns 2// Set all...
Searches for an element that matches the conditions defined by a specified predicate, and returns the zero-based index of the first occurrence within an Array or a portion of it.
This method is an O(n) operation, wherenis the number of elements fromstartIndexto the end ofarray. See also Exists<T>(T[], Predicate<T>) Find<T>(T[], Predicate<T>) FindLast<T>(T[], Predicate<T>) FindAll<T>(T[], Predicate<T>) ...
This method is an O(n) operation, wherenis the number of elements fromstartIndexto the end ofarray. See also Exists<T>(T[], Predicate<T>) Find<T>(T[], Predicate<T>) FindLast<T>(T[], Predicate<T>) FindAll<T>(T[], Predicate<T>) ...