The map.entries() function in D3.js used to return an array of key-value objects for the entry in the created map.
Syntax:
d3.map.entries();
Parameters: This function does not accept any parameter.
Return Value: This function returns an array of key-value pair for the entry in the created map.
Below programs illustrate the d3.map.entries() function in D3.js:
Example 1:
<!DOCTYPE html> <html> <head> <title>d3.map.entries() Function</title> </head> <body> <script> // Creating a map var map1 = d3.map({ "a" : 1}); var map2 = d3.map({ "GFG" : 5}); // Calling the map.entries() function A = map1.entries(); B = map2.entries(); // Getting the array of key value pair console.log(A); console.log(B); </script> </body> </html> |
Output:
[{"key":"a", "value":1}] [{"key":"GFG", "value":5}]
Example 2:
<!DOCTYPE html> <html> <head> <title>d3.map.entries() Function</title> </head> <body> <script> // Creating a map var map1 = d3.map({ "Ram" : 5}, { "Geek" : 10}); var map2 = d3.map(); // Calling the map.entries() function A = map1.entries(); B = map2.entries(); // Getting the array of key value pair console.log(A); console.log(B); </script> </body> </html> |
Output:
[{"key":"Ram", "value":5}] []
Note: Map2 was null that is why it’s became blank.
Reference: https://devdocs.io/d3~5/d3-collection#map_entries