Get the value of an the input on an other input filed

Hello
I m bigginer on PhpMaker and asking for support
How can i get the value of an input filed into an other input filed
Example :
I have 3 input : price, tax, amount
Amount = price * tax. Amount shoud be readonly and shown to the user
How can i do this with the phpmaker
Thanks

Just refer to the demo project file that you can download and test it in your localhost. You may see it in action from “orderdetails” table.