ut2/lib/toNumber.js

一个现代 JavaScript 实用工具库。[点击查看在线文档]。

'use strict';

var isObject = require('./isObject.js');
var isSymbol = require('./isSymbol.js');

var reIsBinary = /^0b[01]+$/i;
var reIsOctal = /^0o[0-7]+$/i;
var reIsBadHex = /^[-+]0x[0-9a-f]+$/i;
function toNumber(value) {
    if (typeof value === 'number') {
        return value;
    }
    if (isSymbol(value)) {
        return NaN;
    }
    if (isObject(value)) {
        value = Number(value);
    }
    if (typeof value !== 'string') {
        return value === 0 ? value : +value;
    }
    value = value.trim();
    var isBinary = reIsBinary.test(value);
    return isBinary || reIsOctal.test(value) ? parseInt(value.slice(2), isBinary ? 2 : 8) : reIsBadHex.test(value) ? NaN : +value;
}

module.exports = toNumber;