Question

我希望建立一个简单的营养计算器，它可以区分一种食物和另一种食物，然后输出营养成分的差异。我无法搞清楚的两件事：

代码似乎工作正常，但是当我增加数量时它返回NaN值，有时只计算为0.
代码只能使用第一个文本框链接值（两个食物项都使用第一个文本框中的值，因此更改第二个文本框中的值不会做任何事情），而且我还没有能够弄清楚如何计算第一个文本框中的单位与另一个文本框中的单位之间的差异。我是否必须为第二个食品创建相同的功能？

我到目前为止的代码：

＆＃13;

var stocks = [
  ["Beef (80/20) raw","oz",115.4451262,2.094125,1.199617347,72,4.85,5.65,0,2.142,19,20,0.0001275510204,0.375,0.75,22.15988372,0.3768292943,4  ],
  ["Beef (90/10) raw","oz",115.4451262,2.094125,1.199617347,50,5.65,2.83,0,1.109,19,18,0.0001275510204,0.375,0.75,22.15988372,0.3768292943,4  ],
  ["Chicken breast","oz",32.39053977,0.320375,0.07197704082,34,6.38,0.74,0,0.16,13,21,0.01631172356,0.10625,0.2125,3.149953226,0.3765300698,4  ],
  ["Chicken thighs/legs","oz",32.39053977,0.320375,0.07197704082,125,2.72,12.54,0,3.431,14,30,0.01631172356,0.10625,0.2125,3.149953226,0.3765799405,4  ],
  ["Milk (whole)","fl oz",7.638924987,0.146025,0.0002099330357,19,0.96,0.99,1.54,0.569,13,0.000000357142857142857,0.099609375,0.19921875,1.228661955,0.2415694159,8  ],
  ["Milk (2%)","fl oz",7.638924987,0.06112164455,0.0002099330357,15,1.06,0.58,1.54,0.363,16,2,0.000000357142857142857,0.099609375,0.19921875,1.228661955,0.2417190282,8  ],
  ["Pizza (cheese)","slice",42,0.9700347449,0.006297991071,285,12.19,10.37,3.83,4.778,640,18,0.00001071428571,2.98828125,5.9765625,36.85985865,0.466697922,4  ],
  ["Ice Cream","cup",32.59312,0.6168324833,0.002345956329,274.71344,4.6095984,14.4806576,27.9835216,8.94913952,107.09168,55.87392,0.000003990994286,1.11311325,2.2262265,13.73003196,2.889031735,1  ],
  ["Milk (skim)","fl oz",7.638924987,0.05927058824,0.0002099330357,10,1.03,0.02,1.54,0.017,13,1,0.000000357142857142857,0.099609375,0.19921875,1.228661955,0.2415694159,8  ],
  ["Eggs (large)","each",43.13341461,0.514206,0.007354326122,78,6.29,5.3,0.2,1.633,62,186,0.001666666667,0.265625,0.53125,3.713549,0.1305756192,1  ],
  ["Lamb","oz",78.125,2.8105,1.199617347,80,4.69,6.64,0,2.889,17,21,0.03333333333,0.3125,0.625,2.274815967,0.3767295528,4  ],
  ["Cheese (hard)","slice (oz)",37.44571072,1.35025,0.002099330357,105,6.59,8.41,0.14,5.32,159,27,0.000003571428571,0.99609375,1.9921875,12.28661955,0.1303337926,1  ],
  ["Yogurt","oz",5.833333333,0.09375,0.0002099330357,17,0.98,0.92,1.32,0.595,13,4,0.000000357142857142857,0.099609375,0.19921875,1.228661955,0.2229453548,6  ],
  ["Greek yogurt, vanilla (nonfat)","fl oz",15,0.08232711306,0.0005248325893,22,2.45,0.05,1.01,0.038,10,1,0.000000892857142857143,0.3984375,0.796875,3.071654888,0.1965527472,6  ],
  ["Chocolate","oz",127.316,0.1862906,0.00004198660714,151,2.16,8.39,14.57,5.238,22,7,0.0000000714285714285714,0.019921875,0.03984375,1.601963425,1.345070603,1.45  ],
  ["Cacao","oz",179.739,0.625,0,136,1.19,8.51,15.45,5.032,3,0,0,0,0,3.390577585,1.418619303,1.45  ],
  ["Salmon (farmed)","oz",0.498125,0.56925,0,59,5.79,3.8,0,0.864,17,16,0.004464285714,0.078125,0.15625,0.5593288054,0.3767295528,4  ],
  ["Tuna (canned in oil)","oz",0.498125,0.1197485281,0,56,8.26,2.33,0,0.435,118,5,0.000270197828,1.0625,2.125,0.5593288054,0.3817664985,4  ],
  ["Mayo","oz",14.41309121,0.121875,0.001838581531,193,0.27,21.22,0.16,3.318,180,12,0.0004166666667,0.06640625,0.1328125,0.92838725,0.1330741748,0.5  ],
  ["Pulled Pork raw","oz",44.84498316,0.63525,0.1411314526,53,4.94,3.5,0,1.232,17,18,0.0005208333333,0.21875,0.4375,1.592371177,0.3767295528,4  ],
  ["Butter (salted)","oz",41.58720633,0.5875,0.00440859375,203,0.24,22.95,0.02,14.537,182,61,0.0000075,2.091796875,4.18359375,25.80190106,0.121322241,1  ],
  ["Soy Burger","oz",21.8,0.048125,0,50,4.44,1.78,0.3,0.408,161,1,0,0,0,2.314125,0.03342563782,4  ],
  ["Vegan Nuggets (soy)","oz",21.8,0.048125,0,52,4.88,1.63,0.65,0.325,172,0,0,0,0,2.314125,0.06360340429,4  ],
  ["Soymilk (original)","fl oz",2.319532348,0.02445449777,0,17,1,0.54,1.21,0.063,16,0,0,0,0,1.168382863,0.1032302684,8  ],
  ["Tofu","oz",25.25,0.09625,0,23,2.82,1.49,0.2,0.26,1,0,0,0,0,4.62825,0.01698083545,4  ],
  ["Tempeh","oz",12.383064,0.0230998152,0,54,5.74,3.06,0,0.719,3,0,0,0,0,1.110771114,0.0001496122504,4  ],
  ["Mixed Nuts","oz",18.72285536,0.18425,0,172,5.53,15.17,1.42,2.271,1,1,0,0,0,1.019662873,0.1202597201,1  ],
  ["Bread","slice",9.735884788,0.1530147137,0,79,3.09,1.31,1.66,0.202,137,0,0,0,0,0.5625,0.1473592997,2  ],
  ["Lentils","oz",30.3684714,0.07425,0,33,2.55,0.11,0.51,0.015,1,0,0,0,0,2.287814892,0.04322383072,7.1  ],
  ["Black Beans","oz",30.3684714,0.141625,0,37,2.31,0.1,0.09,0.025,1,0,0,0,0,1.555714169,0.007668804863,7.1  ],
  ["Tomato Sauce","oz",3.13704,0.09375,0,11,0.47,0.06,1.37,0.008,57,0,0,0,0,0.4188459746,0.1188197409,8  ],
  ["Pinto Beans","oz",30.3684714,0.141625,0,40,2.55,0.18,0.09,0.038,0,0,0,0,0,0.9075003086,0.007618934113,7.1  ],
  ["French Fries","oz",2.9337142,0.0417335921,0,56,0.82,1.91,0.14,0.359,113,0,0,0,0,0.4200133922,0.01748707005,4  ],
  ["Peanut Butter","oz",36,0.2145,0,167,6.81,14.13,2.97,2.153,138,0,0,0,0,3.675378676,0.2583069893,1  ],
  ["Olive Oil","oz",21.77842536,0.2306145384,0,250,0,28.3,0,3.908,1,0,0,0,0,1.512500057,0.00004987075014,0.5  ],
  ["Banana","1 medium",6.440662244,0.1763699536,0,105,1.29,0.39,14.43,0.132,1,0,0,0,0,0.1768995697,1.221618974,1  ],
  ["Mixed vegetables","oz",2.41150377,0.125,0,18,0.81,0.04,0,0.009,10,0,0,0,0,3,0.0004987075014,4  ],
  ["Nutritional Yeast","g",0.08506329224,0.00706361088,0,3.9859577,0.5989518739,0,0,0,0,0,0,0,0,0,0,5  ],
  ["Rice (white)","oz",25.46308329,0.34375,0,102,1.87,0.16,0,0.045,0,0,0,0,0,0.3995205753,0,2  ],
  ["Potatoes","oz",1.872285536,0.03575,0,16,0.73,0.03,0.2,0.007,3,0,0,0,0,0.06927480776,0.01708057695,5.3  ],
  ["Vegetable Oil","oz",17.70433203,0.125,0,205,0,23.8,0,19.937,0,0,0,0,0,5.300817694,0,0.5  ],
  ["Wheat (flour)","1/4 cup",10.11034189,0.03087703323,0,102,3.39,0.47,0.09,0.069,1,0,0,0,0,0.3995205753,0.007668804863,1  ],
  ["Margarine","oz",9.915624199,0.06125,0,102,0.28,11.32,0,2.048,222,0,0,0,0,5.300817694,0.01107130653,1  ],
  ["Corn Syrup","fl oz",11.15931776,0.01728062914,0,109,0,0,29.31,0,1,0,0,0,0,0.4854914297,2.481282747,1  ],
  ["Sugar","oz",11.23371322,0.01503093504,0,110,0,0,28.3,0,0,0,0,0,0,0.4340729937,2.395731504,1  ],
  ["Corn (grain)","oz",6.74022793,0.0104375,0,103,2.67,1.34,0.18,0.189,10,0,0,0,0,0.4549631935,0.01573657573,1  ],
  ["Soda","fl oz",10.64647779,0.02494335117,0,13,0,0.08,3.05,0,1,0,0,0,0,0.1939638153,0.2582470824,12  ]
]

function Stock (data) {
  return {
    name: data[0],
    servingUnit: data[1],
    calories: [data[5], ''],
    protein: [data[6], 'g'],
    fat: [data[7], 'g'],
    saturatedFat: [data[8], 'g'],
    sugar: [data[9], 'g'],
    sodium: [data[10], 'mg'],
    cholesterol: [data[11], 'mg']
  }
}

stocks = stocks.map(Stock)

var $selects = $('.selectStock')
var $quantity = $('#numberOfStocks')
var $comparisonResult = $('.comparison .result')

$selects.each(function() {
  $(this).append(stocks.map(function(stock, i) {
    return new Option(stock.name, i)
  }))
})

function format(data, multiplier, digits) {
  data[0] = (+(data[0] * multiplier).toFixed(digits)).toLocaleString()
  return data.join(' ')
}

function stockFacts(stock, quantity) {
  return [
    format(stock.calories, quantity, 2) + ' calories<br>' +
    format(stock.protein, quantity, 2) + ' of protein<br>' +
    format(stock.fat, quantity, 3) + ' of fat<br>' +
    format(stock.saturatedFat, quantity, 2) + ' of saturated fat<br>' +
    format(stock.sugar, quantity, 2) + ' of sugar<br>' +
    format(stock.sodium, quantity, 2) + ' of sodium<br>' +
    format(stock.cholesterol, quantity, 2) + ' of cholesterol<br>'
  ]
}

$selects.add($quantity).on('input', updateAmount)

function getStock (select) {
  return stocks[+select.value]
}

function updateAmount() {
  var quantity = +$quantity.val()
  
  // Not sure what this line was supposed to do
  if (quantity < 0) quantity = stock[17]
    
  $selects.each(function() {
    var $result = $(this).nextAll('.result').empty()
    var $amount = $(this).prev().find('.servingUnit').empty()
    var stock = getStock(this)
    if (!stock) return
    
    $amount.text(' (' + quantity + ' ' + stock.servingUnit + ')')
    
    $result.html(stockFacts(stock, quantity))
  })
  
  var selectedStocks = [].map.call($selects, getStock)
  $comparisonResult.empty()
  if (!selectedStocks[0] || !selectedStocks[1]) return
  var diff = {}
  Object.keys(selectedStocks[0]).forEach(function (k) {
    if (/^(name|servingUnit)$/.test(k)) return
    var first = selectedStocks[0][k]
    var second = selectedStocks[1][k]
    diff[k] = [Math.abs(first[0] - second[0]), first[1], first > second ? 'more' : 'less']
  })
  $comparisonResult.html(stockFacts(diff, quantity))
}

＆＃13;

  .side {
  float:left;
  margin: 0.5%;
  width: 33%;
  
}
.sideone {
  float:middle;
  margin: 0.5%;
  width: 33%;
  position:relative;
  clear:both;
}
.mid {
  float:middle;
  margin: 0.5%;
  width: 33%;
}
.comparison {
  float:right;
  width:66%;
  position:relative;
  display: inline-block;
}

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<head>
  <meta name="viewport" content="width=10px, initial-scale=1.0">
</head>

<body>
  <label>
    <div class = "side">
    Amount:
    <input type="number" id="numberOfStocks" value="1" min="0" />
    </div>
    <br>
    <br>
    <br>
    <br>
  </label>

  <div>
    <div class="sideone">
      <h2>First Item<span class="servingUnit"></span>:</h2>
      <select class="selectStock">
        <option value="-1">Pick a food!</option>
      </select>
    </div>
    <label>
    <div class = "side">
      Amount:
    <input type="number" id="numberOfStocks" value="1" min="0" />
    </div>
    <br>
    <br>
    <br>
    <br>
  </label>
    <div class="sideone">
      <h2>Second Item<span class="servingUnit"></span>:</h2>
      <select class="selectStock">
        <option value="-1">Pick a food!</option>
      </select>
      <br>
      <br>
    </div>
    <div class="comparison side">
      <h2>Comparison:</h2>
      <br>
      <br>
      <div class="result"></div>
    </div>
  </div>
</body>

＆＃13;

真的很感谢这方面的帮助/指导。非常感谢！

Answer 1

请注意这个插件： https://plnkr.co/edit/AwaiAKQYJHlbvzvRYDqi

完全披露


我尽量不改变你的代码，只修复了上面提到的两个问题。

如果我可以添加，不必过多理解代码。

如果计算出现问题，我没有修复也没试图理解它们。

您的问题的答案：

我添加了一个函数，用于删除以后使用float parseToFloatWithoutCommas(str)计算的格式化数字中的逗号。
我将两个文本框ID's更改为class，就像使用select框一样，因为您无法使用相同的ID一旦进入HTML，但class可以：）

享受; - ）

从下拉菜单输出差异时获取空值？（JavaScript）的

1 个答案:

从下拉菜单输出差异时获取空值？ （JavaScript）的

1 个答案:

从下拉菜单输出差异时获取空值？（JavaScript）的