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废话不多说，看代码！！！

let arr = [
    { userId: 1, name: '小红' },
    { userId: 3, name: '小黄' },
    { userId: 2, name: '小绿' },
    { userId: 1, name: '小蓝' },
    { userId: 2, name: '小紫' },
    { userId: 3, name: '小黑' }
];

// 双指针 + splice方法
function doubleForFilterArr(list, key) {
    for (let i = 0; i < list.length - 1; i++) {
        for (let j = i + 1; j < arr.length; j++) {
            if (list[i][key] === list[j][key]) {
                list.splice(j, 1)
                j--
            }
        }
    }
    return arr
}
const newArr = doubleForFilterArr(arr, 'userId')
console.log(newArr)

// every 去重
function forEachFilterList(list, key) {
    let temp = []
    list.forEach(item => {
        let check = temp.every(t => t[key] !== item[key])
        check ? temp.push(item) : ''
    })
    return temp
}
console.log(forEachFilterList(arr, 'userId'))

//filter去重
function mapFilterList(list, key) {
    let map = new Map()
    for (let item of list) {
        if (!map.has(item[key])) {
            map.set(item[key], item)
        }
    }
    return [...map.values()]
}
console.log(mapFilterList(arr, 'userId'))

// reduce 去重
function reduceFilterList(list, key) {
    let object = {}
    list = list.reduce((a, b) => {
        object[b[key]] ? '' : object[b[key]] = a.push(b)
        return a
    }, [])
    return list
}
console.log(reduceFilterList(arr, 'userId'))

// filter 去重
function filterList(list, key) {
    let newList = []
    newList = list.filter(item => !newList.includes(item[key]))
    return newList
}

console.log(filterList(arr, 'userId'))

数组对象中去重的方式还有很多，可以在评论区讨论一下，谢谢观看，记得点赞 + 收藏！！！