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從下拉菜單輸出差異時獲取空值？ （Javascript）

2017-04-15 64 views
2

我在尋找建立一個簡單的營養計算器，將一種食物和另一種食物之間的差異，然後輸出營養成分的差異。有兩件事情我無法搞清楚：從下拉菜單輸出差異時獲取空值？ （Javascript）

  1. 的代碼看起來工作正常，但是當我增加它返回NaN值，有時只是計算它爲0
  2. 的代碼量是唯一能使用第一個文本框來鏈接值（兩個食品都使用第一個文本框中的值，所以第二個文本框中的值不會做任何改變），我還沒有弄清楚如何計算單位之間的差異在第一個文本框和另一個文本框中的單位。我是否必須爲第二個食品創建相同的功能？

代碼我到目前爲止有：

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>

真的很感謝這個幫助/指導。謝謝一堆！

來源

2017-04-15 Dick Thompson

回答

2

敬請收看普拉克：https://plnkr.co/edit/AwaiAKQYJHlbvzvRYDqi

全面披露

  • 我試着不要太多改變你的代碼，並且只固定兩個提到的問題。
  • 如果我可以添加，而不太瞭解代碼。
  • 如果計算有問題，我沒有修正，也沒有嘗試去理解它們。

的問題的答案：

  1. 我增加了一個功能，從後來被它float parseToFloatWithoutCommas(str)計算格式的數字刪除逗號。

  2. 我換了兩個文本框ID's到class，就像你與select盒，因爲你不能使用相同的ID更多，一旦在HTML，但class可以:)

享受;-)

來源

2017-04-16 11:05:33 EfiBN

+0

湯普森先生，記得接受答案，如果它幫助你，謝謝;-) – EfiBN

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