How to get the main base64 value from reader.result?
I am successful in getting the base64 value of my file but with the value am also getting the type of file and the type of string but I don’t want that. I just want the actual value as I need to send it to the backend.
Code to convert file to base64
handleUpload(e) { var reader = new FileReader(); const file = (e.target as HTMLInputElement).files[0]; reader.readAsDataURL(file); reader.onload = () => { console.log(reader.result as string); }; } 
I want the value starting from ‘U’ after the ‘base64,’ word.
You can simply use a RegExp for that:
reader.result.replace(/^.+?;base64,/, '') But as mentioned in a comment, you should also consider posting the binary as it is, without needing the conversion dance.
const file = (e.target as HTMLInputElement).files[0]; const body = new FormData; body.append('file', file); fetch('/end-point', { method: 'POST', body }); This way is both faster and more efficient, as base64 size is bigger than binary, and there’s no need to wait for the client to convert the binary file.
