JS输入验证

<input type="text" name="userPhone" placeholder="请输入手机号"  class=""  onkeyup="value=value.replace(/[^\d]/g,'')"/>

$("input[name=userPhone]").keydown(function(event){
	var e = event ? event :(window.event ? window.event : null);
	var currKey=e.keyCode||e.which||e.charCode;
	if(currKey == 8){
		 return true;
	}
	if($(this).val().length <11){
		 return (/[\da-i`]/.test(String.fromCharCode(event.keyCode)));	
	}else{
		return false;
	}
});