使用 Javascript 设置最大数量值答案

【问题标题】：Setting a maximum quantity value with Javascript使用 Javascript 设置最大数量值
【发布时间】：2021-02-08 00:32:09
【问题描述】：

我有这个 javascript 来防止数量字段低于 1。我想做的是确保最大数量是 10 并且不能低于 1。

/**
   * When using the quantity selector, this can be used to decrease the quantity (be ensuring it won't be lower than 1)
   */

}, {
  key: '_decreaseQuantity',
  value: function _decreaseQuantity(event, target) {
    target.nextElementSibling.value = Math.max(parseInt(target.nextElementSibling.value) - 1, 1);
  }

  /**
   * When using the quantity selector, this can be used to increase the quantity
   */

}, {
  key: '_increaseQuantity',
  value: function _increaseQuantity(event, target) {
    target.previousElementSibling.value = parseInt(target.previousElementSibling.value) + 1;
  }

  /**
   * Make sure the quantity does not go below when manually changed
   */

}, {
  key: '_validateQuantity',
  value: function _validateQuantity(event, target) {
    target.value = Math.max(parseInt(target.value) || 1, 1);
  }
}]);

【问题讨论】：

标签： javascript html validation math shopify

【解决方案1】：

复制你已经做的以防止值低于 1 就足够了。

{
  key: '_decreaseQuantity',
  value: function _decreaseQuantity(event, target) {
    target.nextElementSibling.value = Math.max(parseInt(target.nextElementSibling.value) - 1, 1);
  }

  /**
   * When using the quantity selector, this can be used to increase the quantity
   */

}, {
  key: '_increaseQuantity',
  value: function _increaseQuantity(event, target) {
    target.previousElementSibling.value = Math.min(parseInt(target.previousElementSibling.value) + 1, 10); // Added check
  }

  /**
   * Make sure the quantity does not go below when manually changed
   */

}, {
  key: '_validateQuantity',
  value: function _validateQuantity(event, target) {
    target.value = Math.min(Math.max(parseInt(target.value) || 1, 1), 10); // Added check
  }
}

【讨论】：