SOURCE

let arr = [
    {
        name:'gwj',
        age:28
    },
    {
        name:'lixian',
        age:33
    },
    {
        name:'lixian',
        age:30
    },
    {
        name:'zhaoliying',
        age:35
    },
    {
        name:'gwj',
        age:28
    }
]

//1.将第一个对象保留

//findIndex返回符合条件的数组的第一个元素索引
let newArr = arr.filter((item,index)=> arr.findIndex(item1 => 
item1.name === item.name) === index)
//newArr
//[{name:'gwj',age:28},{name:'lixian',age:33},{name:'zhaoliying',age:35}]
let newArr1 = arr.filter((item,index)=>arr.findIndex(item1 => 
item1.name === item.name && item.age === item1.age) === index)
//newArr1
//[{name:'gwj',age:28},{name:'lixian',age:33},{name:'lixian',age:30},{name:'zhaoliying',age:35}]



//2.从唯一数组中排除重复项

//find返回符合条件的数组的第一个元素的值（与findIndex类似）
let newArr2 = []
for(let item of arr){
    let isExist = newArr2.find(obj => obj.name === item.name)
    if(!isExist){
        newArr2.push(item)
    }
}
//newArr2
//[{name:'gwj',age:28},{name:'lixian',age:33},{name:'zhaoliying',age:35}]