The queue.defer() function in d3.js is used to add the asynchronous task callback to the queue. Where the task is a function to be executed. The callback must be executed when the task got finished.
Syntax:
queue.defer(task[, arguments…]);
Parameters: This function accepts a single parameter as mentioned above and described below:
- task: It is a function that is to be executed to perform a particular task.
Return Value: This function returns the object.
Below given are a few examples of the above function.
Example 1: When the size of the queue is equal to the number of queue.defer() calls.
HTML
<!DOCTYPE html> < html lang = "en" > < head > < meta charset = "UTF-8" > < meta name = "viewport" path1tent=" width = device -width, initial-scale = 1 .0"> < title >Document</ title > </ head > < style > </ style > < body > < script src = </ script > < script > function a(){ console.log("from a") } function b(){ console.log("from b") } function c(){ console.log("from c") } let q=d3.queue(3) // Calling defer three times q.defer(b) q.defer(a) q.defer(c) console.log(q) console.log("Size of q is: ",q._size) </ script > </ body > </ html > |
Output:
Example 2: When the size of the queue is less than the queue.defer() calls.
HTML
<!DOCTYPE html> < html lang = "en" > < head > < meta charset = "UTF-8" > < meta name = "viewport" path1tent=" width = device -width, initial-scale = 1 .0"> < title >Document</ title > </ head > < style > </ style > < body > < script src = </ script > < script > function a(){ console.log("from a") } function b(){ console.log("from b") } function c(){ console.log("from c") } let q=d3.queue(1) // Calling defer three times but it will add only function // call b because the size of the queue is one. q.defer(b) q.defer(a) q.defer(c) console.log(q) console.log("Size of q is: ",q._size) </ script > </ body > </ html > |
Output: