JS 判断字符串是否全部为数字

val = "123456"
var isnum = /^d+$/.test(val);
document.write(isnum);
document.write("<br>");

val2 = "1232232"
var isnum2 ;
var reg = /^[0-9]+.?[0-9]*$/
isnum2=reg.test(val2);

document.write(isnum2);