Javascript splice 1 code#

This is an optional method, and if you don't want to delete the existing values of the array, its value must be zero or negative. It is a figure which defines how many cells must be deleted after startIndex. At the same time, if the number is greater than the length of the array, it will add new values to the end of the array, automatically increasing its length.Īlso, the delCount parameter can be added to the method. If this parameter is set as a negative number, it will start counting from the end of the array. It must be a positive number (or equal to 0), but this method can handle other values as well. The first (and always required) parameter is startIndex it's defining the index of the array element from which new values will be added. Accordingly, it performs insertion of values sequentially, starting from the specified cell. There are two parameters here that determine the script for inserting new values and the ability to specify data for insertion. Parameters that affect the execution of this command will be in brackets. SyntaxĪrray.splice() must be specified in relation to an array whose contents will be changed.

It is also important to note that during execution of this method, changes will be applied directly to the original array, so check the syntax of parameters carefully. After adding new data, the method will re-index the elements, automatically increasing (or decreasing) the length of the array to the required value and removing empty cells (if they appear).

It is most efficient to add data to the beginning or middle part of an array. The splice() method allows you to add one or more elements sequentially to an existing array. It's better to use the built-in Array method called splice(), which does the same thing just in one line of code. But this is complicated and non-optimized. The most obvious way is to create a new array, then add new data and synchronize different versions of the array.

Javascript splice 1 code#

But during code execution we may need to add new data to the array cells that are already occupied, without deleting the existing ones. In most cases, arrays are filled sequentially, starting from the first cell with a zero index. In JavaScript, arrays are a convenient way to keep data united by an argument in an organized manner. Operators: Addition assignment operator (+=).