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I am dynamically inserting the jQuery library on a page via <script> tag:

jq = document.createElement('script');
jq.setAttribute('src','//ajax.googleapis/ajax/libs/jquery/1.7.1/jquery.min.js');
b.appendChild(jq);

Then I have some jQuery script that needs to run after the jQuery library has finished loading and is ready for use:

$(f).load(function() {
    $(f).fadein(1000);
});

How can I make it wait for jQuery to load?

I am dynamically inserting the jQuery library on a page via <script> tag:

jq = document.createElement('script');
jq.setAttribute('src','//ajax.googleapis./ajax/libs/jquery/1.7.1/jquery.min.js');
b.appendChild(jq);

Then I have some jQuery script that needs to run after the jQuery library has finished loading and is ready for use:

$(f).load(function() {
    $(f).fadein(1000);
});

How can I make it wait for jQuery to load?

• javascript
• jquery
• events
• onload
• jquery-events

Share Improve this question Follow edited Jun 7, 2020 at 15:22 Brian Tompsett - 汤莱恩 5,8937272 gold badges6161 silver badges133133 bronze badges asked Jan 14, 2012 at 18:30 Web_DesignerWeb_Designer 74.6k9393 gold badges209209 silver badges266266 bronze badges 1

• Rob's answer below is perfect, though let me shimmy on here that what you're doing is (a good) part of what Modernizr was made for. :D – Richard Neil Ilagan Commented Jan 14, 2012 at 19:25

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1 Answer 1

Sorted by: Reset to default 14

Specify an onload event at the to-be-inserted script tag:

function onLoad() {
    $(f).load(function() {
        $(f).fadein(1000);
    });
}

jq = document.createElement('script');
jq.onload = onLoad;   // <-- The magic
jq.src = '//ajax.googleapis./ajax/libs/jquery/1.7.1/jquery.min.js';
b.appendChild(jq);

An alternative way, if you cannot control the script insertion code, you can use a poller:

(function() {
    function onLoad() { ... } // Code to be run

    if ('jQuery' in window) onLoad();
    else {
        var t = setInterval(function() { // Run poller
            if ('jQuery' in window) {
                onLoad();
                clearInterval(t);        // Stop poller
            }
        }, 50);
    }
})();

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