JS modify the key value of the object array

example ： take dataOld Properties in the object of this object array key become dataNew In the form of ;

// The original data 
dataOld: [{ count: '33', area: '122.2', districtId: 43000 }, { count: '44', area: '168.2', districtId: 43001 }] 
// Data required by the interface 
dataNew: [{ countAll: '33', countArea: '122.2', districtId: 43000 }, { count: '44', area: '168.2', districtId: 43001 }]

Method 1 ： Use map loop , stay map Create a new object in the loop , take item To change key Assign new to the newly created object key value , then push Give a newly created array dataNew that will do ;

let dataNew = [];    // New array 
dataOld.map(item => {
    let obj = {
        countAll: item.count,
        countArea: item.area,
        districtId: item.districtId,
    }
     dataNew.push(obj);
});

Method 2 ： Use map loop + replace Replace , Pass the loop and then subclass JSON.stringify After using replace To change properties key;

let dataNew = [];    // New array 
dataOld.map(item => {
    let _item = JSON.parse(JSON.stringify(item).replace('count', 'countAll').replace('area', 'countArea'));
    dataNew.push(_item)
});

Method 3 ： Use forEach loop + for loop , adopt Object.keys() To change properties key;

convertKey (arr, key) {
    let dataNew = []; // New array 
    this.dataOld.forEach((item, index) => {
        let obj = {}; // New object in new array 
        for (var i = 0; i < key.length; i++) {
            obj[key[i]] = item[Object.keys(item)[i]]; //key Value substitution   
        }
        dataNew.push(obj);
    })
    console.log(dataNew,'dataNew');
    return dataNew;
},
                                            //  After the change key
let dataNew = this.convertKey(this.dataOld, ['countAll', 'countArea', 'districtId']);

result ：