js 把数组转换成对象

var arr = [

['username', 'jack'],

['age', 18],

['gender', '男']

]

转换成 {usename: 'jack', age: 18, gender: '男'}

var obj = {}

for (var i = 0; i < arr.length; i++) {

for (var j = 0; j < arr[i].length; j++) {

// console.log(arr);

// console.log(arr[i][j]);

obj[arr[i][0]]=arr[i][1]

}

}