How can I create a dropdown menu in the hero section of a Webflow website that is preselected based on the ad that brought the user there?

To create a dropdown menu in the hero section of your Webflow website that is preselected based on the ad that brought the user there, follow these steps:

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1. Add a Dropdown Menu in Webflow

• Navigate to the Webflow Designer for the page where you want to add the dropdown.
• Add a Dropdown element to your hero section from the Add Elements panel.
• Customize the dropdown items as needed with appropriate options that correspond with your ads.

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2. Modify the URL for Each Ad

• For each ad, modify the URL to include a query parameter that reflects the desired preselection (e.g., ?adsource=option1, ?adsource=option2).
• Ensure each ad that's bringing users to your site has a unique query parameter attached.

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3. Use Custom Code to Preselect Dropdown

• In the Webflow Designer, go to Page Settings for the relevant page.
• Scroll to the Custom Code section and insert a custom script in the Before Body Tag area.
• Use JavaScript to:
• Read the query parameter from the URL to determine which ad brought the user to this page.
• Select the corresponding option in the dropdown menu based on the query parameter.

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4. Implement the JavaScript Code

• Insert the following code snippet to achieve the preselection:

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document.addEventListener("DOMContentLoaded", function() {
    // Get URL parameter
    const urlParams = new URLSearchParams(window.location.search);
    const adSource = urlParams.get('adsource');

    // Get the dropdown element
    const dropdown = document.querySelector('select'); // Adjust selector as necessary

    // Preselect option if parameter matches
    if (dropdown && adSource) {
        const optionToSelect = dropdown.querySelector(`option[value="${adSource}"]`);
        if (optionToSelect) {
            optionToSelect.selected = true;
        }
    }
});

• Adjust the selector if your dropdown menu uses a specific class or ID.

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Summary

By modifying ad destination URLs to include query parameters and using JavaScript to read these parameters, you can effectively preselect the appropriate dropdown option based on which ad brought the user to your Webflow page.