want to use input to enter the time (format 00:00). If you fill in 8:45, fill in 0 before, and fill in automatically in the middle:, now there are more than one after: the front does not automatically fill 0
<div class="layui-inline">
<label class="layui-form-label"></label>
<div class="layui-input-inline layui-form">
<input type="text" maxlength="5" onkeyup="regVal(event)" autocomplete="off" class="layui-input">
</div>
</div>
function regVal(ev) {
if (ev.altKey || ev.ctrlKey || ev.shiftKey || ev.metaKey ) return;
var str = ev.target.value.replace(/[^\d]/g,"").replace(/(.{2,2})/g, "$1:");
if (str === ev.target.value) return;
ev.target.value = str;
} 