Test the processing performance of JavaScript strings.

It mainly tests the actual processing of the JS engine performance of the array push () method and the directly adding method. The program code is simple and easy to explain. Note: The number of cycles must be large enough.

Copy to ClipboardReference: [www.bkjia.com] var oldtime = new Date (). getTime ();
Var str = [];
For (I = 0; I <100000; I ++)
{
Str. push ('abcabcabcabcabcabcabcabcabcabcabcabcabc ');
}
Var newtime = new Date (). getTime ();
Var joinTime = (newtime-oldtime );

Var oldtime = new Date (). getTime ();
Var str = '';
For (I = 0; I <100000; I ++)
{
Str + = 'abcabcabcabcabcabcabcabcabcabcabcabcabcabc ';
}
Var newtime = new Date (). getTime ();
Var concatTime = (newtime-oldtime );

Alert ("join/concat:" + (joinTime * 1.0/concatTime ));