JavaScript_code_snippets/unique_array.html at master · dendoink/JavaScript_code_snippets · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>7种数组去重的方法</title>
</head>

<body>

</body>
<script>
    const unique_forloop = (array) => {
        let len = array.length
        let result = [array[0]]
        for (let i = 1; i < len; i++) {
            if (!result.includes(array[i])) {
                result.push(array[i])
            }
        }
        return result
    }
    const unique_index_filter = (array) => {
        return array.filter((item, index) => {
            return array.indexOf(item) === index
        })
    }
    const unique_splice = (array) => {
        let temp = array.sort()
        for (let i = 0; i < temp.length; i++) {
            debugger
            if (temp[i] === temp[i + 1]) {
                temp.splice(i, 1)
                i--
            }
        }
        return temp
    }
    const unique_array_reduce = (array) => {
        return array.reduce((preResult, current) => {
            if (!preResult.includes(current)) {
                preResult.push(current)
            }
            return preResult
        }, [])
    }
    const unique_array_from_set = (array) => {
        return Array.from(new Set(array))
    }
    const unique_array_set = (array) => {
        return [...new Set(array)]
    }
    const unique_object_property = (arr) => {
        var obj = {};
        return arr.filter(function (item, index) {
            // typeof item + item  是为了避免将不同类型但是转换后值相等的元素去除。
            return obj.hasOwnProperty(typeof item + item) ? false : (obj[typeof item + item] = true)
        })
    }
    // let n = unique_array_reduce([1, 1, 2, 2, 3, 4, 5, 1])
    // let n = unique_forloop([1, 1, 2, 2, 4, 3, 5, 1])
    // let n = unique_index_filter([1, 1, 2, 2, 4, 3, 5, 1])
    // let n = unique_array_set([1, 1, 2, 2, 4, 3, 5, 1])
    let n = unique_object_property(['1', 1, 2, 2, 4, 3, 5, 1])
    console.log('n: ', n);
</script>

</html>