How to lowercase of input field in onkeyup event?

Script Method:
<input type="text" id="ele" onkeyup="this.value=this.value.toLowerCase()" >
CSS Method:
Add style "text-transform:uppercase"
<input type="text" id="ele" style='text-transform:lowercase' >

How to uppercase of input field in onkeyup event?

Script Method:
<input type="text" id="ele" onkeyup="this.value=this.value.toUpperCase()" >
CSS Method:
Add style "text-transform:uppercase"
<input type="text" id="ele" style='text-transform:uppercase' >