JS输入带空格的银行卡
document.getElementById("yhk").value=document.getElementById("yhk").value.replace(/\s/g,'').replace(/(\d{4})(?=\d)/g,"$1 ");
document.getElementById("yhk").value=document.getElementById("yhk").value.replace(/\s/g,'').replace(/(\d{4})(?=\d)/g,"$1 ");