Several methods to use JS to delete one or more items in an array
Below I will bring you several methods in JS to delete one or more items in an array. Let me share it with you now and give it as a reference for everyone.
1. The splice method in js
splice(index,len,[item]) Note: This method will change the original array.
splice has 3 parameters, it can also be used toreplace/delete/addone or several values in the array
index: array start index len: Length of replacement/deletion item: replacement value, if the deletion operation occurs, the item will be empty
For example: arr = ['a','b','c','d']
Delete---- item is not set
arr.splice(1,1) //['a','c','d'] The deletion starting index is 1 , a value with a length of 1, len is set to 1, if it is 0, the array remains unchanged
arr.splice(1,2) //['a','d'] A value marked as 1, with a length of 2, replaced by 2
set by len---- item is the replaced value
arr.splice(1,1 ,'ttt') //['a','ttt','c','d'] Replace the starting subscript with 1, a value with length 1 as 'ttt', and the len setting as 1
arr.splice(1,2,'ttt') //['a','ttt','d'] Replace the two values with starting subscript 1 and length 2 as 'ttt', len is set to 1
add---- len is set to 0, item is the added value
arr.splice(1,0,'ttt') / /['a','ttt','b','c','d'] means adding an item 'ttt' at the subscript 1
It seems that splice is the most convenient
2, delete After delete deletes the element in the array, it will set the subscripted value to undefined, The length of the array will not change
For example: delete arr[1] //['a', ,'c','d'] There are two commas in the middle, the length of the array remains unchanged, and one item is undefined
The above is what I compiled for everyone. I hope it will be helpful to everyone in the future, and I also hope everyone will support the PHP Chinese website.
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