Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
684 views
in Technique[技术] by (71.8m points)

floating point - Integers in JavaScript

I'm a beginner to Javascript so forgive me if I sound dumb because I learned some Javascript from W3Fools (which are really difficult tutorials - they don't explain anything I want to know, but everything I probably can guess from my experience with C++).

I may be switching over to MDN, but if you can recommend any other tutorials, that be great.

Anyways, so here's my question:

I just read a few lines of this, and apparently:

Numbers in JavaScript are "double-precision 64-bit format IEEE 754 values", according to the spec. This has some interesting consequences. There's no such thing as an integer in JavaScript, so you have to be a little careful with your arithmetic if you're used to math in C or Java.

I've already seen that there are few of the data types (for variables) I'm used to from C++. But I didn't expect all numbers to automatically be floats. Isn't there any way to use integers, not float? Will a future version of JavaScript support ints?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

There are really only a few data types in Javascript: Objects, numbers, and strings. As you read, JS numbers are all 64-bit floats. There are no ints.

Firefox 4 will have support for Typed Arrays, where you can have arrays of real ints and such: https://developer.mozilla.org/en/JavaScript_typed_arrays

Until then, there are hackish ways to store integer arrays as strings, and plucking out each integers using charCodeAt().


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...