This is a very basic problem, but we often do something wrong. Here we will share it with you to make it easier for a friend who needs to clear an array. Many people use the following method:
The Code is as follows:
A = [];
We know that javascript variable storage methods can be divided into reference types and direct quantities. The array belongs to the object, that is, the reference type. It references the variable pointer address, which is designed to save memory.
In addition, if the preceding empty array method is used to assign a new array directly, the previously referenced array may not be released (with other references ), for example, the following code:
The Code is as follows:
Var a = [2, 3];
Var B =;
A = [];
Console. log (B );
At this time, a and B are not the same array. After a is cleared, B still refers to the referenced address. unless you mean it, this will pose a risk.
Therefore, the best way to empty the array is to set the length to 0, that is:
The Code is as follows:
A. length = 0;
