1. 方法概述
Array的sort()方法默认把所有元素先转换为String再根据Unicode排序，
sort()会改变原数组，并返回改变（排序）后的数组 。
2. 例子
2.1 如果没有提供自定义的方法， 数组元素会被转换成字符串，并返回字符串在Unicode编码下的顺序比较结果
var fruit = [‘cherries‘, ‘apples‘, ‘bananas‘]; fruit.sort(); // [‘apples‘, ‘bananas‘, ‘cherries‘] var scores = [1, 10, 2, 21]; scores.sort(); // [1, 10, 2, 21] // Watch out that 10 comes before 2, // because ‘10‘ comes before ‘2‘ in Unicode code point order. var things = [‘word‘, ‘Word‘, ‘1 Word‘, ‘2 Words‘]; things.sort(); // [‘1 Word‘, ‘2 Words‘, ‘Word‘, ‘word‘] // In Unicode, numbers come before upper case letters, // which come before lower case letters.
2.2 利用map来排序
// the array to be sorted var list = [‘Delta‘, ‘alpha‘, ‘CHARLIE‘, ‘bravo‘]; // temporary array holds objects with position and sort-value var mapped = list.map(function(el, i) { return { index: i, value: el.toLowerCase() }; }) // sorting the mapped array containing the reduced values mapped.sort(function(a, b) { return +(a.value > b.value) || +(a.value === b.value) - 1; }); // container for the resulting order var result = mapped.map(function(el){ return list[el.index]; }); alert(result);
参考 https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort
原文：http://www.cnblogs.com/rocky-fang/p/5757772.html