The d3.keys() function in D3.js is used to return an array containing the property names or keys of the specified object or an associative array.
Syntax:
d3.keys(object)
Parameters: This function accepts single parameter object containing key and value in pairs.
Return Value: It returns the keys of the given object.
Below programs illustrate the d3.keys() function in D3.js:
Example 1:
<!DOCTYPE html> <html> <head> <title>
d3.keys() Function
</title>
</head> <body> <script>
// Initialising an object
var month = {
"January": 1,
"February": 2,
"March": 3,
"April": 4
};
// Calling the d3.keys() function
A = d3.keys(month);
// Getting the key values of the given object
document.write(A);
</script>
</body> </html> |
Output:
January, February, March, April
Example 2:
<!DOCTYPE html> <html> <head> <title>
d3.keys() Function
</title>
</head> <body> <script>
// Initialising an object
var month = {
"GeeksforGeeks": 0,
"Geeks": 2,
"Geek": 3,
"gfg": 4
};
// Calling the d3.keys() function
A = d3.keys(month);
// Getting the key values of the given object
document.write(A);
</script>
</body> </html> |
Output:
GeeksforGeeks, Geeks, Geek, gfg
Reference: https://devdocs.io/d3~5/d3-collection#keys