es6 箭头函数 map、find var value = arr.map(function (x) {return x * x}); const arr = [1,2,3,4]; const value = arr.map(x => x * x); //value = {[[1,1],[2,4],[3,9],[4,16]]} nationArr = [{'id':1,'name':'汉族'},...] this.nationArr.find(n => n.name === '汉族').id = 1