javascript - 如何在 JavaScript 的 for 循环中创建动态变量以返回 json？

Question

我调用的 API 有一部分我需要拉取成分，然后推送到 html 页面。它们被列为 strIngredient1、strIngredient2、strIngredient3...直到 15。我想要做的是循环遍历每种成分？我认为我需要某种动态变量。完全不确定。

for (var x = 1; x < 16; x++) {
  if ((drinkResponse.drinks[0].strIngredient + x) !== null) {
    $("#drinkOutput").append($("<p class='drinkData'>Drink Ingredient" + x + " : " + (drinkResponse.drinks[0].strIngredient + x) + "</p>"))
  }
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>

这就是我想要做的想法，但目前它返回 NaN；当它应该返回一个字符串时。

JSON 返回:

drinks[0] {

  dateModified: "2017-09-02 16:38:19"

  idDrink: "11224"

  strAlcoholic: "Alcoholic"

  strCategory: "Ordinary Drink"

  strCreativeCommonsConfirmed: "No"

  strDrink: "Casino Royale"

  strDrinkAlternate: null

  strDrinkDE: null

  strDrinkES: null

  strDrinkFR: null

  strDrinkThumb: "https://www.thecocktaildb.com/images/media/drink/3qpv121504366699.jpg"

  strDrinkZH-HANS: null

  strDrinkZH-HANT: null

  strGlass: "Whiskey sour glass"

  strIBA: null

  strIngredient1: "Gin"

  strIngredient2: "Lemon juice"

  strIngredient3: "Maraschino liqueur"

  strIngredient4: "Orange bitters"

  strIngredient5: "Egg yolk"

  strIngredient6: null

  strIngredient7: null

  strIngredient8: null

  strIngredient9: null

  strIngredient10: null

  strIngredient11: null

  strIngredient12: null

  strIngredient13: null

  strIngredient14: null

  strIngredient15: null

  strInstructions: "In a shaker half-filled with ice cubes, combine all of the ingredients. Shake well. Strain into a sour glass."

  strInstructionsDE: "In einem Shaker, der halb mit Eiswürfeln gefüllt ist, alle Zutaten vermengen. Gut schütteln. In ein Sour Glas abseihen."

  strInstructionsES: null

  strInstructionsFR: null

  strInstructionsZH-HANS: null

  strInstructionsZH-HANT: null

  strMeasure1: "2 oz "

  strMeasure2: "1/2 oz "

  strMeasure3: "1 tsp "

  strMeasure4: "1 dash "

  strMeasure5: "1 "

  strMeasure6: null

  strMeasure7: null

  strMeasure8: null

  strMeasure9: null

  strMeasure10: null

  strMeasure11: null

  strMeasure12: null

  strMeasure13: null

  strMeasure14: null

  strMeasure15: null

  strTags: null

  strVideo: null

}

Answer 1

您正在尝试将值 x 附加到变量名称。您很接近，但您需要使用括号表示法而不是点表示法。

例如，如果x当前为5，您可以通过drinkResponse.drinks[0]['strIngredient'+x]获取strIngredient5的值 或 drinkResponse.drinks[0][`strIngredient${x}`]。

正如 Lain 指出的，您还可以使用 Object.keys 枚举对象上的所有键，然后仅过滤以 strIngredient 开头的键:

// get all keys on the drink
const allKeys = Object.keys(drinkResponse.drinks[0]);

// now filter for only keys starting with `strIngredient`
const ingredients = allKeys.filter(key => key.startsWith('strIngredient'));

for (const i=0; i<ingredients.length; i++) {
    $("#drinkOutput").append($("<p class='drinkData'>Drink Ingredient" 
    + i + " : " + (drinkResponse.drinks[0][ingredients[i]]) + "</p>"))
}

请注意，这可能不会保留顺序，但您可以通过组合前两个示例来保留顺序:

for (const i=0; i<ingredients.length; i++) {
    $("#drinkOutput").append($("<p class='drinkData'>Drink Ingredient" 
    + i + " : " + (drinkResponse.drinks[0][`strIngredient${i}`]) + "</p>"))
}