我希望构建一个简单的营养计算器，它可以计算一种食物和另一种食物之间的差异，然后输出营养成分的差异。我无法弄清楚两件事:
- 代码似乎工作正常，但当我增加数量时，它会返回 NaN 值，有时只是将其计算为 0。
- 代码只能使用第一个文本框来链接值(两种食物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执行任何操作)，而且我无法弄清楚了解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函数？
我到目前为止的代码:
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))
} .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;
}<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>非常感谢对此的帮助/指导。非常感谢!
最佳答案
请观看此视频: https://plnkr.co/edit/AwaiAKQYJHlbvzvRYDqi
Full Disclosure
- I tried not to much changing your code, and only fix the two mentioned problems.
- If I may add, without too much understand the code.
- If there are problems with calculations, I didn't fixed nor tried to understand them.
您的问题的答案:
我添加了一个函数，用于从稍后用它计算的格式化数字中删除逗号
float parseToFloatWithoutCommas(str)。我将两个文本框
ID's更改为class，就像您对select框所做的那样，因为您无法使用在HTML中可以使用相同的ID，但class可以:)
享受;-)
关于javascript - 从下拉菜单输出差异时获取空值？ (Javascript)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/43429319/