How Can I Manage Concurrent jQuery AJAX Requests and Ensure All Complete Before Proceeding?

Managing Concurrent jQuery AJAX Requests

When handling multiple concurrent AJAX requests, it can be necessary to pause execution until all requests are complete. This ensures that subsequent operations rely on data retrieved from all requests.

Solution: Utilizing jQuery's $.when Function

jQuery introduces a convenient function called $.when. It takes multiple Deferred objects as arguments (representing ongoing AJAX requests) and executes a callback function when all of them resolve.

Implementation

To execute an action after all AJAX requests complete:

$.when(ajax1(), ajax2(), ajax3(), ajax4()).done(function(a1, a2, a3, a4){
    // Code to be executed after all requests resolve
});

Here, ajax1(), ajax2(), ajax3(), and ajax4() are functions returning Deferred objects representing the AJAX requests.

Example AJAX Function

function ajax1() {
    return $.ajax({
        url: "someUrl",
        dataType: "json",
        data: yourJsonData        
    });
}

Advantages of Using $.when

• Avoids involving global variables and potential side effects.
• Provides a clean and concise syntax.
• Allows for easy failure handling by calling .then() or .fail() on the Promise object returned by $.when.

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