JSFiddle - React, Tailwind, and code Playground
HTML
<input type="text" maxlength="10" id="myInput">
JavaScript
var input = document.getElementById("myInput");
input.onkeypress = function(e) { e = e || window.event;
var charCode = (typeof e.which == "number") ? e.which : e.keyCode;
// Allow non-printable keys
if (!charCode || charCode == 8 /* Backspace */ ) {
return;
}
var typedChar = String.fromCharCode(charCode);
// Allow numeric characters
if (/\d/.test(typedChar)) {
return;
}
// Allow the minus sign (-) if the user enters it first
if (typedChar == "-" && this.value == "") {
return;
}
// In all other cases, suppress the event
return false;
};