For flexibility and other places you might want to validated. You can use the following function.
`function validateOnlyTextField(element) {
var str = element.value;
if(!(/^[a-zA-Z, ]+$/.test(str))){
// console.log('String contain number characters');
str = str.substr(0, str.length -1);
element.value = str;
}
}`
Then on your html section use the following event.
<input type="text" id="names" onkeyup="validateOnlyTextField(this)" />
You can always reuse the function.