Call Parent Javascript Function From Inside An Iframe

If you're a web developer working with iframes in your projects, you may have encountered the need to call a JavaScript function from inside an iframe up to its parent document. This task might seem tricky at first, but fear not, as I'm here to guide you through the process step by step.

To achieve this functionality, you need to understand how JavaScript handles interactions between parent and child documents containing iframes. The key concept here is the `window.parent` property, which allows you to access the parent window from within an iframe.

First and foremost, ensure that both the parent document and the iframe content are served from the same domain. This is a crucial security measure imposed by the same-origin policy to prevent cross-site scripting attacks.

Now, let's delve into the code. Suppose you have an iframe embedded within the parent document and you want to trigger a function defined in the parent document from within the iframe. Here's how you can achieve this:

<!-- Parent document (parent.html) -->



    <title>Parent Document</title>


    

    
        function parentFunction() {
            console.log("Function called from child iframe!");
        }

In the parent document above, we have a simple JavaScript function named `parentFunction()` that we want to call from within the iframe. The iframe source is set to `child.html`, where we'll implement the code to trigger the parent function.

Next, let's look at the code inside the iframe document:

<!-- Child document (child.html) -->



    <title>Child Document</title>


    <button>Call Parent Function</button>

    
        function callParentFunction() {
            window.parent.parentFunction();
        }

In the child document above, we have a button that, when clicked, invokes the `callParentFunction()` JavaScript function. Inside this function, we use `window.parent` to access the parent document's window object and call the `parentFunction()` defined in the parent document.

By using the `window.parent` property, you establish a communication channel between the parent and child documents, enabling you to trigger functions defined in the parent from within the iframe.

Remember, proper error handling is crucial when working with cross-origin communication between parent and child documents. Always ensure that your code gracefully handles scenarios where the parent function may not exist or if there are any permission issues due to the same-origin policy.

With these steps and code snippets, you should now be equipped to effectively call a parent JavaScript function from inside an iframe in your web projects. Happy coding!