JavaScript 减少，无法处理对象数组

Question

我正在尝试在对象数组上处理此规则如果存在一个或多个类型等于固定电话的对象，则返回第一个数字，否则如果不存在类型=固定电话的对象，则仅当其类型属性与移动电话不同时才返回第一个数字，如果其等于移动电话，则返回下一个数字如果可用，否则返回空白值

var phoneObject = [
  {
    type: 'mobile',
    phone: '0123456789'
  },
  {
    type: 'mobile',
    number:'78945610'
  }
  {
    type:'landline'
    number:'15975345'
  }
];

var number = phoneObject.reduce((a,b)=>{
  if (a.type === 'landline' && b.type === 'landline') {
    b.number = a.number;
  }
  else {
    if (a.type !== 'landline' && b.type !== 'landline') {
      if (a.type !== 'mobile') {
        b.number = a.number;
      } else {
        if (b.number) {
          return b.number;
        }
        else {
          b.number = '';
        }
      }
    }
  }
  return b.number;
});
console.log(number);

// should return the third number for this array
var phoneObject = [
  {
    type: 'mobile',
    phone: '0123456789'
  },
  {
    type: 'mobile',
    number:'78945610'
  }
  {
    type:'landline'
    number:'15975345'
  }
];


// for this one it should return the first 
var phoneObject = [
  {
    type: 'landline',
    phone: '0123456789'
  },
  {
    type: 'mobile',
    number:'78945610'
  }
  {
    type:'landline'
    number:'15975345'
  }
];

// for this one it should return the second number
  {
    type: 'mobile',
    phone: '0123456789'
  },
  {
    type: 'mobile',
    number:'78945610'
  }
];

// and for this last one it should return a blank value
var phoneObject = [
  {
    type: 'mobile',
    phone: '0123456789'
  },
];

感谢您的帮助此致，莎拉

Answer 1

您可以进行一些适当的检查并保存第二个数字。仅当没有固定电话号码时才使用它。

此提案适用于 Array#reduce 。

function getNumber(array) {
    var counter = 0,
        second = '';
    return array.reduce(function (r, o) {
        if (r) {
            return r;
        }
        if (o.type === 'landline') {
            return o.number;
        }
        counter++;
        if (counter === 2) {
            second = o.number;
        }
    }, '') || second;
}

//should return the third number for this array
var phoneObject1 = [{ type: 'mobile',  number: '0123456789' }, { type: 'mobile', number:'78945610' }, { type: 'landline', number:'15975345' }];

// for this one it should return the first 
var phoneObject2 = [{ type: 'landline', number: '0123456789' }, { type: 'mobile', number:'78945610' }, { type:'landline', number:'15975345' }];

// for this one it should return the second number
var phoneObject3 = [{ type: 'mobile', number: '0123456789' }, { type: 'mobile', number:'78945610' }];

//and for this last one it should return a blank value
var phoneObject4 = [{ type: 'mobile', number: '0123456789' }];

console.log([phoneObject1, phoneObject2, phoneObject3, phoneObject4].map(getNumber));

与上面相同，但使用 Array#some

function getNumber(array) {
    var counter = 0,
        landline = '',
        second = '';

    array.some(function (o) {
        if (o.type === 'landline') {
            landline = o.number;
            return true;
        }
        counter++;
        if (counter === 2) {
            second = o.number;
        }
    });
    return landline || second;
}

//should return the third number for this array
var phoneObject1 = [{ type: 'mobile',  number: '0123456789' }, { type: 'mobile', number:'78945610' }, { type: 'landline', number:'15975345' }];

// for this one it should return the first 
var phoneObject2 = [{ type: 'landline', number: '0123456789' }, { type: 'mobile', number:'78945610' }, { type:'landline', number:'15975345' }];

// for this one it should return the second number
var phoneObject3 = [{ type: 'mobile', number: '0123456789' }, { type: 'mobile', number:'78945610' }];

//and for this last one it should return a blank value
var phoneObject4 = [{ type: 'mobile', number: '0123456789' }];

console.log([phoneObject1, phoneObject2, phoneObject3, phoneObject4].map(getNumber));