问如果Javascript函数再次被调用，如何杀死它？

EN

<input type="checkbox" onclick="fire()" >CB1
<br />
<input type="checkbox" onclick="fire()" >CB2

function_lock = false

fire = function() {
    // First, check the lock isn't already reserved. If it is, leave immediately.
    if (function_lock) return;

    // We got past the lock check, so immediately lock the function to 
    // stop others entering
    function_lock = true;

    console.log("This message will appear once, until the lock is released")

    // Do your work. I use a simple Timeout. It could be an Ajax call.
    window.setTimeout(function() {
        // When the work finishes (eg Ajax onSuccess), release the lock.
        function_lock = false;
    }, 2000);
}

<input type="checkbox" onclick="doAjax()" >CB2

ajax_lock = false

doAjax: function() {
    // Check the lock.
    if (ajax_lock) return;

    // Acquire the lock.
    ajax_lock = true;

    // Do the work.
    $.get("url to ajax endpoint", function() {
         // This is the success function: release the lock
         ajax_lock = false;
    });   
} 

function processStuff() {
    var dfd = $.Deferred();

    // do some processing, when finished, 
    // resolve the deferred object
    window.setTimeout(function(){
        dfd.resolve();
    }, 2000);

    return dfd.promise();
}

function startProcessing() {
    $('#processingCheckbox').attr('disabled', 'disabled');
     var promise = processStuff();    
    promise.done(enableCheckbox);
}

function enableCheckbox() {
    $('#processingCheckbox').removeAttr('disabled');
}

$('#processingCheckbox').on('click', startProcessing);