How to delete an element from js array
How to delete an element from a js array requires specific code examples
In JavaScript, if we need to delete an element from an array, there are several ways to do it accomplish. These methods are described in detail below and corresponding code examples are provided.
- Using the splice() method
The splice() method allows us to remove elements from an array and replace them with other elements if necessary. It accepts two parameters: the index position of the element to be removed and the number of elements to be removed.
The following is a code example of using the splice() method to delete an element:
var fruits = ["apple", "banana", "orange"]; fruits.splice(1, 1); // 删除索引为1的元素,即删除"banana" console.log(fruits); // 输出:["apple", "orange"]
- Using the filter() method
The filter() method allows us to pass an element Filter the array with a condition and return a new array. We can use this method to filter out the elements we want to delete.
The following is a code example of using the filter() method to delete an element:
var fruits = ["apple", "banana", "orange"]; fruits = fruits.filter(function(value) { return value !== "banana"; // 返回不等于"banana"的元素 }); console.log(fruits); // 输出:["apple", "orange"]
- Using the delete keyword
The delete keyword can be used to delete objects Properties, because arrays are also special types of objects in JavaScript, we can also use the delete keyword to delete elements in the array. However, it should be noted that using the delete keyword to delete elements will not change the length of the array, and will set the deleted elements to undefined.
The following is a code example of using the delete keyword to delete an element:
var fruits = ["apple", "banana", "orange"]; delete fruits[1]; // 删除索引为1的元素,即删除"banana" console.log(fruits); // 输出:["apple", undefined, "orange"]
It should be noted that although the delete keyword can be used to delete elements, we do not recommend it. This method removes an element from an array because it leaves a hole (undefined).
The above are several common methods to delete an element in an array in JavaScript. You can choose the appropriate method to delete elements in the array according to your needs.
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