The map.remove() function is an inbuilt function in D3.js. If the created map contains the given key string then it removes the entry and returns true. If key string not presents then it returns false.
Syntax:
map.remove(key)
Parameters: This function accepts single parameter key which is used to specify the key string.
Return Value: This function returns true if the created map has an entry for the specified key string otherwise returns false.
Below programs illustrate the d3.map.remove() function in D3.js:
Example 1:
<!DOCTYPE html> <html> <head> <title>d3.map.remove() function</title>
</head> <body> <script>
// Creating a map
var map = d3.map({"Ram": 5, "Geeks": 10, "gfg": 15});
// Calling the map.remove() function
A = map.remove("Ram");
B = map.remove("Geek");
C = map.remove("Geeks");
// Getting true if the map has an
// entry for the specified key string
// otherwise returns false.
console.log(A);
console.log(B);
console.log(C);
</script>
</body> </html> |
Output:
true false true
Example 2:
<!DOCTYPE html> <html> <head> <title>d3.map.remove() function</title>
</head> <body> <script>
// Creating some maps
var map1 = d3.map({"Ram": 5});
var map2 = d3.map({"Geeks": 10});
var map3 = d3.map({"Ram": 5, "Geeks": 10});
var map4 = d3.map();
// Calling the map.remove() function
A = map1.remove("Ram");
B = map2.remove("Geek");
C = map3.remove("Shyam");
D = map4.remove("Ram");
// Getting true if the map has an
// entry for the specified key string
// otherwise returns false.
console.log(A);
console.log(B);
console.log(C);
console.log(D);
</script>
</body> </html> |
Output:
true false false false
Ref: https://devdocs.io/d3~5/d3-collection#map_remove