input type="file" - accept files without any extension

Question

how do I accept files without any extension?
I need to accept .json and no-extension files
I tried

<input type="file" accept=".json, . "/>  

and some variations of it with dot and empty space, but none of them work

Answer 1

There is no such feature in HTML file input yet.If you want it you can develop this feature either by serverside progamming or javascript validation. Accept all format files and Validate format and find desired formats and restrict all other formats.