Change Some Marketo Hidden Field Values Depending on Another Field's Value

marketoCustomFormValues.js

// http://developers.marketo.com/javascript-api/forms/
/* Using Forms 2.0 from Landing Pages

While all of the forms examples use embedded forms, the same APIs are available on Marketo Landing Pages as well.

Usually, you’ll want to add a script that gets some reference to the form object. To do this, first add your form to the landing page, then add a new HTML block to your landing page. Then you can add a script block to the page as follows */

MktoForms2.whenReady(function (form) {
	var selectedPackage, Marketing_Asset_Id_Current__c, last_mkt_asset, Company_Size_Range__c_account, formTrialPackageType;

	// http://developers.marketo.com/rest-api/assets/forms/examples/
	// Add onSubmit handler
	form.onSubmit(function(){
		// when user clicks a "package" radio button, get the selected package
		selectedPackage = $("[name='formTrialPackageType']").val();

		// depending on the package value, set asset ID and company size values
		switch(selectedPackage) {
			case "Express Lite":
				Marketing_Asset_Id_Current__c = "307";
				last_mkt_asset = "307";
				Company_Size_Range__c_account = "1-250";
				break;
			case "Express":
				Marketing_Asset_Id_Current__c = "306";
				last_mkt_asset = "306";
				Company_Size_Range__c_account = "251-5000";
				break;
			case "Enterprise":
				Marketing_Asset_Id_Current__c = "305";
				last_mkt_asset = "305";
				Company_Size_Range__c_account = "5000+";
				break;
			case "Consultant":
				Marketing_Asset_Id_Current__c = "308";
				last_mkt_asset = "308";
				Company_Size_Range__c_account = "Security Consultant";
				break;
		}

		// update hidden field values
		$("[name='Marketing_Asset_Id_Current__c']").val(Marketing_Asset_Id_Current__c);
		$("[name='last_mkt_asset']").val(last_mkt_asset);
		$("[name='Company_Size_Range__c_account']").val(Company_Size_Range__c_account);

		// use this block during testing to display values in the console
		// remove this block in production
		// Check if the form is submittable
		if (form.submittable()) {
			// Set it to be non submittable
			form.submittable(false);
			console.log("Marketing_Asset_Id_Current__c = " + $("[name='Marketing_Asset_Id_Current__c']").val());
			console.log("last_mkt_asset = " + $("[name='last_mkt_asset']").val());
			console.log("Company_Size_Range__c_account = " + $("[name='Company_Size_Range__c_account']").val());
		}
	});
});