The following example usesindexOfto find all the indices of an element in a given array, usingpushto add them to another array as they are found. varindices = []; varidx = array.indexOf(element); while(idx != -1) { indices.push(idx); idx = array.indexOf(element, idx + 1); }...
Here is an example of how you can use the indexOf() method to find the index of an element in an int array: int[] array = {1, 2, 3, 4, 5}; int index = Arrays.indexOf(array, 3); // index is 2 Copy Alternatively, you can use a loop to search for the element in the...
You can use the findIndex value like this, which runs a function for each item in the array, which is passed the element, and its index. Returning from it will assign the return value to the return value of findIndex:const letters = [ { letter: 'a', }, { letter: 'b', }, { ...
输出: 1 程序2: // Taking input as an array A// having some elements.varname = ['gfg','cse','geeks','portal'];//indexOf() method is called to// test whether the searching element// is present in given array or not.a = name.indexOf('cat')// Printing result of methoddocument....
arr[2] = 'mango'; document.getElementById('output').innerHTML = 'Array : ' + arr; Try Online Conclusion In thisJavaScript Tutorial, we learned how to access elements of an Array in JavaScript, with examples.
我从myarray.indexOf(element) 得到 -1,即使元素似乎在 myarray 中。 下面是一些代码片段: {代码...} 警报显示 nds 确实包含 el,但警报应该只在 idx==-1 时触发,只有当 nds 不包含 el 时才会触发。 我知道我...
In Java, when working with arrays, there is no built-inindexOf()method, as you might find in other programming languages like JavaScript. However, you can achieve this functionality by converting your array to anArrayListand then using theindexOf()method on theArrayList. ...
const array = [NaN]; array.indexOf(NaN); // -1 找出指定元素出现的所有位置 jsCopy to Clipboard const indices = []; const array = ["a", "b", "a", "c", "a", "d"]; const element = "a"; let idx = array.indexOf(element); while (idx !== -1) { indices.push(idx); ...
所以Array.prototype.includes也不区分+0和-0,当然也可以检测NaN: [-0].includes(+0)// true[NaN].includes(NaN)// true[NaN].indexOf(NaN)// -1 具体的相等比较运算符差异请参阅 [MDN - Equality comparisons and sameness](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Equality_comparison...
This JavaScript tutorial explains how to use the Array method called findIndex() with syntax and examples. In JavaScript, findIndex() is an Array method that is used to return the index of the first element in the array that meets a specific criteria.