1.7 KiB
1.7 KiB
id, title, challengeType, videoUrl, localeTitle
id | title | challengeType | videoUrl | localeTitle |
---|---|---|---|---|
56bbb991ad1ed5201cd392ce | Manipulate Arrays With unshift() | 1 | 使用unshift操作数组() |
Description
shift
元件关闭的阵列的开头的,也可以unshift
元素添加到数组的开始,即在阵列的前添加元素。 .unshift()
工作方式与.push()
完全相同,但是不是在数组的末尾添加元素, unshift()
会在数组的开头添加元素。 Instructions
unshift()
将["Paul",35]
添加到myArray
变量的开头。 Tests
tests:
- text: '<code>myArray</code>现在应该有[[“Paul”,35],[“dog”,3]]。'
testString: 'assert((function(d){if(typeof d[0] === "object" && d[0][0] == "Paul" && d[0][1] === 35 && d[1][0] != undefined && d[1][0] == "dog" && d[1][1] != undefined && d[1][1] == 3){return true;}else{return false;}})(myArray), "<code>myArray</code> should now have [["Paul", 35], ["dog", 3]].");'
Challenge Seed
// Example
var ourArray = ["Stimpson", "J", "cat"];
ourArray.shift(); // ourArray now equals ["J", "cat"]
ourArray.unshift("Happy");
// ourArray now equals ["Happy", "J", "cat"]
// Setup
var myArray = [["John", 23], ["dog", 3]];
myArray.shift();
// Only change code below this line.
After Test
console.info('after the test');
Solution
// solution required