The fastest and best way to splice HTML strings in javascript_javascript tips

First type: Add strings one by one

Copy code The code is as follows:

var arr = ['item 1', 'item 2 ', 'item 3', ...];
list = '';
for (var i = 0,
l = arr.length; i < l; i ) {
list = '' arr[i] '';
}
list = '' list '';

This is the most common, but the least efficient! The code logic is relatively complex.

Second type: push into the array one by one

Copy code The code is as follows:

var arr = ['item 1', 'item 2 ', 'item 3', ...],
list = [];

for (var i = 0,
l = arr.length; i < l; i ) {
list[list.length] = '' arr[i] '';
}
list = '' list.join('') '';

Slightly faster than the previous method, but still not good enough...

Third method: direct join()

Copy code The code is as follows:

var arr = ['item 1', 'item 2 ', 'item 3', ...];

var list = '' arr.join('') '';

Using native methods (such as join()), no matter how it is implemented later, is generally much faster than other methods, and the code is very concise.

Browser performance test

Each method is tested using an array with a length of 130, in which the length of each element is varied to prevent the browser from making special optimizations for strings of a certain length; each method was tested 1,000 times ;The following results show the time required to execute these 1000 times: