JS Input Quantity Control

<div class= "W-number" >

<a class= "w-number-btn w-number-btn-minus" pro= "Minus" href= "javascript:void (0);" >-</a>

<input class= "w-number-input" pro= "input" type= "text" value= "5" >

<a class= "w-number-btn w-number-btn-plus" pro= "plus" href= "javascript:void (0);" >+</a>

</div>

Window. One_goods = {
Status:1,
period:304080621,
Goods: {
gid:1851,
Gname: ' Golden Peace ',
price:3688,
Buyable:true,
Buyunit:10
},
existingtimes:3485
};

Quantity Input Box window. One_goods
var $numInput = $ (". W-number-input");
var obuynum = parseint ($numInput. Val ());
//-
$ (". W-number-btn.w-number-btn-minus"). Click (function () {
var buynum = $numInput. val ()-$numInput. Val ()% One_goods.goods.buyunit-one_goods.goods.buyunit;
Obuynum = Buynum >= ONE_GOODS.goods.buyUnit? BuyNum:ONE_GOODS.goods.buyUnit;
$numInput. Val (obuynum);
});
//+
$ (". W-number-btn.w-number-btn-plus"). Click (function () {
var buynum = parseint ($numInput. Val ())-$numInput. Val ()% ONE_GOODS.goods.buyUnit + ONE_GOODS.goods.buyUnit;
Obuynum = Buynum <= one_goods.existingtimes? BuyNum:ONE_GOODS.existingTimes;
$numInput. Val (obuynum);
});
Input
$numInput. Hover (function () {SelectText ($numInput [0],0, $numInput. Val (). length);},function () {});
$ (". W-number-input"). Change (function () {
var buynum = $numInput. val ();
if (/^\d+$/.test (Buynum)) {
if (Buynum < ONE_GOODS.goods.buyUnit) {
Obuynum = ONE_GOODS.goods.buyUnit;
}else if (Buynum > One_goods.existingtimes) {
Obuynum = One_goods.existingtimes;
}else if (Buynum%one_goods.goods.buyunit > 0) {
Obuynum = buynum > ONE_GOODS.goods.buyUnit? Buynum-buynum% ONE_GOODS.goods.buyUnit + ONE_GOODS.goods.buyUnit:ONE_GOODS.goods.buyUnit;
}
}
$numInput. Val (obuynum);
});

JS Input Quantity control