JavaScript数组对象去重的几种实现方式

    let repeatData = [
      { id: 1, name: 'sun', age: 18 },
      { id: 1, name: 'sun', age: 18 },
      { id: 2, name: 'baozi', age: 20 },
      { id: 1, name: 'sun', age: 18 },
      { id: 3, name: 'lele', age: 3 },
      { id: 2, name: 'baozi', age: 20 }
    ]

利用Map对象去重

   // 利用map对象
   let map = new Map()
   repeatData.forEach(item => {
     map.set(item.id, item)
   })
   let newData = [...map.values()]
   console.log(newData, 'newData');

双层for循环去重

   for (let i = 0; i < repeatData.length; i++) {
     for(let j = i + 1; j < repeatData.length; j++) {
       if (repeatData[i].id === repeatData[j].id) {
         repeatData.splice(j, 1)
         j--
       }
     }
   }
   console.log(repeatData, 'repeatData');

利用reduce方法去重

   let newObj = {}; 
   repeatData = repeatData.reduce((preVal, curVal) => {
     newObj[curVal.id] ? '' : newObj[curVal.id] = preVal.push(curVal);
     return preVal 
   }, [])
   console.log(repeatData, 'repeatData');

利用对象属性去重

   let newObj = {}, newArr = []
   repeatData.forEach(item => {
     if (!newObj[item.id]) {
       newObj[item.id] = newArr.push(item)
     }
   })
   console.log(newArr, 'newArr');