JavaScript writes a timer

I am new to JavaScript and wrote a timer in JavaScript.

Design idea:

1. Use the Date() object to continuously obtain time points;

2. Then subtract the milliseconds of the two time points to calculate the time difference;

3. Accumulate the time difference, so that Can keep time accurately.

ps:

I haven’t seen this method on the Internet. Generally, setinterval is used. The delay and time control that come with the programming language have relatively large errors;

So use the system time subtraction method. The control is precise, and in this example, the three-digit millisecond number is displayed to verify the accuracy. The setting is 100 milliseconds, and Js itself will have errors;

This program can avoid inaccuracy problems.

This example is for mutual communication, and we are eager to get readers’ ideas and suggestions.

< ;button type="button" onclick="timer('ptime')">
Start timing