Javascript override for “Place Order button” using custom Woocommerce payment gateway
Here's the entire JavaScript you need to inject into the page:
jQuery( function($) { $("form.woocommerce-checkout") .on('submit', function() { return gatewayFunction( this ); } ); } );The outer jQuery( function($) { and } ); make sure that the code in between only gets run when the HTML document is loaded (that way the the <form> will exist by the time that code will run), and makes jQuery available as $ in between.
The return gatewayFunction( this ) passes the <form> to the function, so it can use it's values and add or update a hidden payment token field, so you'll need to add that parameter to the gatewayFunction:
function gatewayFunction( form ) { ... return is_payment_complete;}