船舶重量计算

Question

我需要根据产品重量来计算船价。

• 船运价格$1重量0-5
• 船价$2重量$6 -1
• 船价$3重量2-3
• 船价$4重量4-5

<航运价格$5重量价格$6重量11-25H 212F 213

如果我输入的重量介于1到10之间，那么航运价格显示的不正确。如何纠正这些错误？

​

function sprice() {
  let a = 0.5;
  let b = 1;
  let c = 3;
  let d = 5;
  let e = 10;
  let f = 25;

  let g = 1; //0-.5
  let h = 2; //.6-1
  let i = 3; //2-3
  let j = 4; //4-5
  let k = 5; //6-10
  let l = 6; //11-25

  let z = 0;
  let inc = 0;

  let p = document.getElementById("number").value;
  let s = 25;

  while (p > 0) {
    if (p <= a) {
      z += g;
    }
    if (p <= b) {
      z += h;
    }
    if (p <= c) {
      z += i;
    }
    if (p <= d) {
      z += j;
    }
    if (p <= e) {
      z += k;
    }
    if (p <= f) {
      z += l;
    }
    ++inc;
    let y = inc * z;
    document.getElementById("ans").innerHTML = "$" + y;
    p -= s;
  }
}

<form>
  Enter Weight:<input type="text" id="number" name="number" /><br />
  <input type="button" value="get" onclick="sprice()" />
</form>
</br>
<p>Shipping Price:<span id="ans"></span></p>

​

Answer 1

您应该能够在这里简化您的逻辑，创建一个函数getShippingPrice()来获取给定重量的发货价格，然后将其添加到总价格中，直到所有权重都计算在内：

​

function sprice()
{  
    let weight = Number(document.getElementById("number").value);
    let s = 25;
    
    let totalPrice = 0;
    while (weight > 0) {
       totalPrice += getShippingPrice(weight);
       weight -= s;
    }    
    document.getElementById("ans").innerHTML = "$" + totalPrice;      
}

function getShippingPrice(weight) {
    if (weight <= 0.5 ) return 1;
    if (weight <= 1 )   return 2;
    if (weight <= 3 )   return 3;
    if (weight <= 5 )   return 4;
    if (weight <= 10 )  return 5;
    return 6;
}

<form>  
Enter Weight:<input type="text" id="number" name="number"/><br/>  
<input type="button" value="get" onclick="sprice()"/>  
</form> </br>   

<p>Shipping Price:<span id="ans"></span></p>

​

Answer 2

逻辑

检查用户输入是否大于25 input

• Calculate (如果是)，如果是的话，则取用户question

• Decrement的相同值，使用if -

• ，如果您的question

• Decrement 25中提到的条件来自用户输入。

• 在循环中运行逻辑，直到用户输入小于零。

您遇到的问题是必须使用else if而不是简单的else，因为如果输入一个值，比如0.1，它满足所有的if条件。总金额将是错误的。此外，您也不必将增量索引乘以与y = (inc*z);相同的值。您只需要继续在循环中添加和，每次减少25次，同时执行循环。

工作部件

​

function sprice() {
  let a = 0.5; let b = 1; let c = 3; let d = 5; let e = 10; let f = 25;

  let g = 1; //0-.5
  let h = 2; //.6-1
  let i = 3; //2-3
  let j = 4; //4-5
  let k = 5; //6-10
  let l = 6; //11-25

  let z = 0;

  let userInput = +document.getElementById("number").value;
  let s = 25;
  let quantity = 0;

  while (userInput > 0) {
    quantity = userInput > s ? s : userInput;
    if (quantity <= a) {
      z += g;
    } else if (quantity <= b) {
      z += h;
    } else if (quantity <= c) {
      z += i;
    } else if (quantity <= d) {
      z += j;
    } else if (quantity <= e) {
      z += k;
    } else if (quantity <= f) {
      z += l;
    }
    userInput -= s;
  }
  document.getElementById("ans").innerHTML = "$" + z;
}

<form>
  Enter Weight:<input type="text" id="number" name="number" /><br />
  <input type="button" value="get" onclick="sprice()" />
</form> </br>

<p>Shipping Price:<span id="ans"></span></p>

​

Answer 3

这里有一个更加干净、可靠和可伸缩的解决方案。我认为代码很简单，所以我不会解释它。但是如果你什么都不懂，请随便问我:)

​

// Add more categories if you need
const categories = [{
    price: 1,
    range: [0, 0.5]
  },
  {
    price: 2,
    range: [0.6, 1]
  },
  {
    price: 3,
    range: [2, 3]
  },
  {
    price: 4,
    range: [4, 5]
  },
  {
    price: 5,
    range: [6, 10]
  },
  {
    price: 6,
    range: [11, 25]
  },
];

const [priceForMaxWeight, maxWeight] = categories.reduce(
  ([maxPrice, maxWeight], category) => {
    const [min, max] = category.range;
    if (min < 0 || max < 0 || min === max || min > max)
      throw new Error(`Invalid range: [${min}, ${max}]`);
    return max > maxWeight ? [category.price, max] : [maxPrice, maxWeight];
  }, [Infinity, -Infinity]
);

function getPrice(weight) {
  const isInRange = (value, [min, max]) => value >= min && value <= max;

  for (let i = 0; i < categories.length; i++) {
    const {
      price,
      range
    } = categories[i];
    if (isInRange(weight, range)) return price;
  }

  throw new Error(`Weight: ${weight} doesn't fall into any category.`);
}

function calculatePrice(weight) {
  if (weight < 0) throw new Error(`Invalid weight: ${weight}`);

  if (weight > maxWeight)
    return priceForMaxWeight + calculatePrice(weight - maxWeight);
  return getPrice(weight);
}

// Interacting with dom
const calculateButton = document.getElementById("btn");
const result = document.getElementById("result");
const weightInput = document.getElementById("weight");

calculateButton.addEventListener("click", () => {
  const weight = Number(weightInput.value);
  result.innerText = calculatePrice(weight) + "$";
});

<p>Enter Weight:</p>
<input id="weight" type="number" min="0" /><br />
<button id="btn">Calculate Price</button>

<p>Price: <span id="result">0$</span></p>

​