将数组转换为对象+设置属性名称

function arrayToObject(arr, propName) {
  var obj = {};
  for (var i = 0; i < arr.length; i++) {
    obj[propName + i] = arr[i];
  }
  return obj;
}

var arr = [1, 2, 3, 4, 5];
var obj = arrayToObject(arr, 'item');
console.log(obj);

function arrayToObject(arr, propName) {
  return arr.reduce(function(obj, item, index) {
    obj[propName + index] = item;
    return obj;
  }, {});
}

var arr = [1, 2, 3, 4, 5];
var obj = arrayToObject(arr, 'item');
console.log(obj);