A button for adding data is displayed multiple times. An error occurred while adding the data. Solution-php Tutorial

A button for adding data is displayed multiple times. An error occurred while adding the data. I would like to explain how to solve this problem, whether to allow them to submit forms without repeating them, or how to do it. please also provide details. ------ Solution ------------------ very simple. let's look at the example & lt; formactiona. phpmethodpostonsubmit & quot; this. action: a button for adding data. multiple times, an error occurred while adding the data.
How can I solve this problem,
Is to keep them from submitting forms repeatedly,
How can I do this,
For more information, see.

------ Solution --------------------
Simple. let's look at the example.


As long as the form action is changed to # After the token is submitted for the first time, it cannot be submitted for the second time.