Dapatkan sejumlah kunci dalam objek javascript

Objek. metode keys() digunakan untuk mengembalikan nama properti objek sebagai array. Properti length digunakan untuk mendapatkan jumlah kunci yang ada di objek. Ini memberikan panjang objek.  

Sintaksis

objectLength = Object.keys(exampleObject).length

Contoh.  

html




<!DOCTYPE html>

<html>

 

<head>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
2
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
3
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
2>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6head>

 

<<!DOCTYPE html>1>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<<!DOCTYPE html>5 <!DOCTYPE html>6<!DOCTYPE html>7<!DOCTYPE html>8<!DOCTYPE html>9<!DOCTYPE html>5>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<<5
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
3<5>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<html2>

html4html5

html6html7

html6html9

html6>1

________90

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_91_______3

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html2>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<html2>

html4 4

html4 6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html2>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<html2>

________90

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_89_______7

________90______4<head0 head1<!DOCTYPE html>7head3head4head0>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html2>

 

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<>4 >5<!DOCTYPE html>7>7>

html_4

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
00

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6>4>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
08>

html_4

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
11

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_12

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
14

html6html5

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
17html7

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
17html9

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
17>1

html6>3

 

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
27

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
29

 

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
32

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_33
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
34

________90

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_91_______3

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
08>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6<!DOCTYPE html>1>

 

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
47

Keluaran

Dapatkan sejumlah kunci dalam objek javascript

Temukan panjang objek JavaScript

Metode 2. Ulangi semua bidang objek dan periksa propertinya

Metode hasOwnProperty() digunakan untuk mengembalikan nilai boolean yang menunjukkan apakah objek memiliki properti yang ditentukan sebagai propertinya sendiri. Metode ini dapat digunakan untuk memeriksa apakah setiap kunci ada di objek itu sendiri. Isi objek dilingkarkan dan jika kuncinya ada, jumlah total kunci bertambah. Ini memberikan panjang objek.  

Sintaksis

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_

Contoh.  

html




<!DOCTYPE html>

<html>

 

<head>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
2
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
3
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
2>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6head>

 

<<!DOCTYPE html>1>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<<!DOCTYPE html>5 <!DOCTYPE html>6<!DOCTYPE html>7<!DOCTYPE html>8<!DOCTYPE html>9<!DOCTYPE html>5>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<<5
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
3<5>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<html2>

html4html5

html6html7

html6html9

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
97

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
99

________90

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_91_______3

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html2>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<html2>

html4 4

html4 6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html2>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<html2>

________90

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_89_______7

________90______4<head0 head1<!DOCTYPE html>7head3head4head0>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html2>

 

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<>4 >5<!DOCTYPE html>7>7>

html_4

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
00

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6>4>

<_2

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0<
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
08>

html_4

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
11

 

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
14

html6html5

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
17html7

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
17html9

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_17
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
97

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_17
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_99

html6>3

 

html6<!DOCTYPE html>77

 

html6<!DOCTYPE html>80

html6<!DOCTYPE html>82

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
17<!DOCTYPE html>84

 

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_33<!DOCTYPE html>87

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_33<!DOCTYPE html>89

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_33<!DOCTYPE html>91

html6>3

html6<!DOCTYPE html>95

 

html6

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
32

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_33
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
34

________90

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
_91_______3

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
0
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
08>

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6<!DOCTYPE html>1>

 

var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
6html
var key, count = 0;

// Check if every key has its own property
for (key in exampleObject) {
    if (exampleObject.hasOwnProperty(key))

        // If the key is found, add it to the total length
        count++;
}
objectLenght = count;
47

Keluaran

Dapatkan sejumlah kunci dalam objek javascript

Temukan panjang objek JavaScript

JavaScript terkenal untuk pengembangan halaman web tetapi juga digunakan di berbagai lingkungan non-browser. Anda dapat mempelajari JavaScript dari awal dengan mengikuti Tutorial JavaScript dan Contoh JavaScript ini

Bagaimana cara mendapatkan jumlah kunci dalam objek JavaScript?

keys() dan properti length digunakan untuk menghitung jumlah kunci dalam suatu objek. Objek. metode keys() mengembalikan array dari nama properti enumerable objek yang diberikan i. e. ["nama", "umur", "hobi"]. Properti length mengembalikan panjang array.

Bagaimana cara mendapatkan jumlah pasangan nilai kunci dalam JavaScript?

Untuk mendapatkan jumlah kunci dalam suatu objek. .
Panggil Objeknya. keys() metode, meneruskan objek sebagai parameter
Akses properti panjang pada hasilnya
Objek. metode kunci mengembalikan array yang berisi kunci objek

Bagaimana cara mendapatkan kunci suatu objek dalam JavaScript?

Bagaimana cara mendapatkan Kunci, Nilai, dan Entri di Objek JavaScript? .
Obyek. keys(obj) – mengembalikan semua kunci objek sebagai larik
Obyek. values(obj) – mengembalikan semua nilai objek sebagai array
Obyek. entri(obj) – mengembalikan larik [kunci, nilai]

Bagaimana cara mendapatkan jumlah properti objek dalam JavaScript?

Gunakan Objek. keys() metode, meneruskan objek yang ingin Anda periksa, untuk mendapatkan array dari semua properti enumerable objek (milik sendiri) .