There is a way to use an inline script to do this:
<input type='text' onkeypress="return (event.charCode > 64 && event.charCode < 91) || (event.charCode > 96 && event.charCode < 123) || (event.charCode == 32)" placeholder="Only alphabets and space is allowed"/>
Demo
See the Pen Allow Letters Only by Puneet Sharma (@webdevpuneet) on CodePen.
You can also use it inside a function and call it on multiple text fields. You can choose whichever way suits you best.
HTML
<input type="text" onkeypress="return onlyAlphabets(event,this);" />
JavaScript
function onlyAlphabets(e, t) {
try {
if (window.event) {
var charCode = window.event.keyCode;
}
else if (e) {
var charCode = e.which;
}
else { return true; }
if ((charCode > 64 && charCode < 91) || (charCode > 96 && charCode < 123 || charCode == 32))
return true;
else
return false;
}
catch (err) {
alert(err.Description);
}
}
See the Pen Validate / Allow Alphabets and space only in text field by Puneet Sharma (@webdevpuneet) on CodePen.