标签:console style span bar pos nts xpl with splice
參考自: https://love2dev.com/blog/javascript-remove-from-array/
1. Removing Elements from End of Array
var ar = [1, 2, 3, 4, 5, 6]; ar.length = 4; // set length to remove elements console.log( ar ); // [1, 2, 3, 4] var ar = [1, 2, 3, 4, 5, 6]; ar.pop(); // returns 6 console.log( ar ); // [1, 2, 3, 4, 5]
2. Removing Elements from Beginning of Array
var ar = [‘zero‘, ‘one‘, ‘two‘, ‘three‘]; ar.shift(); // returns "zero" console.log( ar ); // ["one", "two", "three"]
3. Using Splice to Remove Array Elements
var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]; var removed = arr.splice(2,2); /* removed === [3, 4] arr === [1, 2, 5, 6, 7, 8, 9, 0] */
["bar", "baz", "foo", "qux"] list.splice(0, 2) // Starting at index position 0, remove two elements ["bar", "baz"] and retains ["foo", "qux"].
4. Removing Array Items By Value Using Splice
var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]; for( var i = 0; i < arr.length; i++){ if ( arr[i] === 5) { arr.splice(i, 1); } } //=> [1, 2, 3, 4, 6, 7, 8, 9, 0]
5. Using the Array filter Method to Remove Items By Value
var array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]; var filtered = array.filter(function(value, index, arr){ return value > 5; }); //filtered => [6, 7, 8, 9] //array => [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
6. The Lodash Array Remove Method
var array = [1, 2, 3, 4]; var evens = _.remove(array, function(n) { return n % 2 === 0; }); console.log(array); // => [1, 3] console.log(evens); // => [2, 4]
7. Making a Remove Method
function arrayRemove(arr, value) { return arr.filter(function(ele){ return ele != value; }); } var result = arrayRemove(array, 6); // result = [1, 2, 3, 4, 5, 7, 8, 9, 0]
8. Explicitly Remove Array Elements Using the Delete Operator
var ar = [1, 2, 3, 4, 5, 6]; delete ar[4]; // delete element with index 4 console.log( ar ); // [1, 2, 3, 4, undefined, 6] alert( ar ); // 1,2,3,4,,6
9. Clear or Reset a JavaScript Array
var ar = [1, 2, 3, 4, 5, 6]; //do stuff ar = []; //a new, empty array! var arr1 = [1, 2, 3, 4, 5, 6]; var arr2 = arr1; // Reference arr1 by another variable arr1 = []; console.log(arr2); // Output [1, 2, 3, 4, 5, 6] var ar = [1, 2, 3, 4, 5, 6]; console.log(ar); // Output [1, 2, 3, 4, 5, 6] ar.length = 0; console.log(ar); // Output [] var ar = [1, 2, 3, 4, 5, 6]; console.log(ar); // Output [1, 2, 3, 4, 5, 6] ar.splice(0, ar.length); console.log(ar); // Output [] var ar = [1, 2, 3, 4, 5, 6]; console.log(ar); // Output [1, 2, 3, 4, 5, 6] while (ar.length) { ar.pop(); } console.log(ar); // Output []
Javacript Remove Elements from Array
标签:console style span bar pos nts xpl with splice
原文地址:https://www.cnblogs.com/sipher/p/11563975.html