Simple Method to Calculate the Hash of a file in Javascript using HTML5 API

ExampleFileMD5.js

//Event Listener tied to the file input field
document.getElementById('attachment').addEventListener('change', eventHandler, false)

/**
*Description:	Simple method to handle an event
*and fire off a function
**/
function eventHandler(evt){
	var file = evt.target.files[0];
		fileHash( file, md5, function(x){
			console.log( x );
		});
	}
	
/**
*Description: The actual function to calculate the hash
*Arguments:
*file:	a file from a file input load event
*hasher:	hashing algorithm
*callback:	function that does something with the hash
**/
	function fileHash( file, hasher, callback ){
		//Instantiate a reader		  
		var reader = new FileReader();
			  
		//What to do when we gets data?
		reader.onload = function( e ){
			var hash = hasher(e.target.result);
			callback( hash );
		}
			
		reader.readAsBinaryString( file );

	}

I'm getting "md5 is not defined". What is md5 in your code? Thank you. (I'm testing in raw html)
See this one, it worked for me:
https://techoverflow.net/2021/11/26/how-to-compute-sha-hash-of-local-file-in-javascript-using-subtlecrypto-api/