JSFiddle - React, Tailwind, and code Playground

HTML

<input  type='text'  onkeyup='check(event);' id='in' />
	
<div id='out' ></div>

JavaScript

function check(e){
		var text = e.keyCode ? e.keyCode : e.charCode;
				 
		 switch(text){
		 case 81:
			text = '&#4632;';
			break;
		case 87:
			text = '&#4633;';
			break;
		case 69:
			text = '&#4634;';
			break;
		case 82:
			text = '&#4635;';
			break;
		case 84:
			text = '&#4636;';
			break;
		case 89:
			text = '&#4637;';
			break;
		case 85:
			text = '&#4638;';
			break;
}
	
	if(text == 8){
		
		var str = document.getElementById("out").innerHTML;
		var foo = str.substring(0, str.length -1);
		document.getElementById("out").innerHTML = foo; 
	}else {
		document.getElementById("out").innerHTML += text;
	}

	}