javascript - 遍历 javascript 对象并根据条件输出某些信息

Question

我有一个对象数组，我想从中获取值：

    lastChanceSeats: Object
      assignedSeats: Array[6]
        0: Object
          SeatId: "29A"
          passengerName: "Mr test1 test1"
          sectorSequence: 1
        1: Object
          SeatId: "22A"
          passengerName: "Mr test1 test1"
          sectorSequence: 2
        2: Object
          SeatId: "29B"
          passengerName: "Mrs test2 test2"
          sectorSequence: 1
        3: Object
          SeatId: "22B"
          passengerName: "Mrs test2 test2"
          sectorSequence: 2
        4: Object
          SeatId: "29C"
          passengerName: "Master test3 test3"
          sectorSequence: 1
        5: Object
          SeatId: "22C"
          passengerName: "Master test3 test3"
          sectorSequence: 2

我想以以下格式显示数据：

• 第一个 {passengerName}
• {sectorSequence: 1} + {SeatId}
• {sectorSequence: 2} + {SeatId}

...然后乘客二、三等也一样。

Answer 1

使用简单的模板并循环遍历每个项目以生成输出：

var data=[
    {
        "SeatId": "29A",
        "passengerName": "Mr test1 test1",
        "sectorSequence": 1
    },
    {
        "SeatId": "22A",
        "passengerName": "Mr test1 test1",
        "sectorSequence": 2
    },
    {
        "SeatId": "29B",
        "passengerName": "Mrs test2 test2",
        "sectorSequence": 1
    }
]


function template(ob, str){
   return str.replace(/{([\w\s.\$]+?)}/g, 
     function(j,a){  return ob[a]||"";  } );
}

strTemplate="First {passengerName}  {sectorSequence} + {SeatId}";

out=$(data).map(function(i,item){ return template(item, strTemplate)}).toArray().join("\n");

alert(out);

/* result:
First Mr test1 test1  1 + 29A
First Mr test1 test1  2 + 22A
First Mrs test2 test2  1 + 29B  */

Answer 2

不可能对对象属性进行有序迭代。

你可以这样做：

var data=[
    {
        "SeatId": "29A",
        "passengerName": "Mr test1 test1",
        "sectorSequence": 1
    },
    {
        "SeatId": "22A",
        "passengerName": "Mr test1 test1",
        "sectorSequence": 2
    },
    {
        "SeatId": "29B",
        "passengerName": "Mrs test2 test2",
        "sectorSequence": 1
    }
], 
orderedObjectProps = ['SeatId', 'passengerName', 'sectorSequence'],
dataLength = data.length,
propsLength = orderedObjectProps.length,
i = 0;

for(i; i < dataLength; i++) {
  var obj = data[i],
  j = 0;
  for(j; j < propsLength; j++) {
    var propName = orderedObjectProps[j],
    propValue = obj[propName];
    console.log(propValue);
  }
}

上面的代码将按照您想要的顺序打印值。

Answer 3

使用与上述答案相同的数据，您可以尝试此代码段

var data=[
    {
        "SeatId": "29A",
        "passengerName": "Mr test1 test1",
        "sectorSequence": 1
    },
    {
        "SeatId": "22A",
        "passengerName": "Mr test1 test1",
        "sectorSequence": 2
    },
    {
        "SeatId": "29B",
        "passengerName": "Mrs test2 test2",
        "sectorSequence": 1
    }
]

function test_iteration(data) {
  data.forEach(e => {
    console.log(`SeatId : ${e.SeatId}`);
    console.log(`passengerName : ${e.passengerName}`);
    console.log(`sectorSequence : ${e.sectorSequence}`);
  })
}
function test_iteration_2(data) {
  data.forEach(e => {
    for (var prop in e) {
      if (Object.prototype.hasOwnProperty.call(e, prop)) {
        console.log(`${prop} : ${e[prop]}`);
      }
    }
  })
}

test_iteration_2(data) ;