Question

我是编程和学习C＃的新手，我有点卡住了。我试图设置两个固定费率和一个可变费率参考以下内容：

5磅或以下的运费为3.50美元，20磅或以下的运费为10美元， [例如：10磅重量：运费是10美元。 4磅重量：3.5 $] 重量超过20磅，每磅9.5加$ 10c。（两种统一费率和一种可变利率）

这就是我现在所拥有的（它一团糟）：

//Declorations

int artDbl, carrDbl, beetDbl;
double resultInt, result1Dbl, result2Dbl,totalresultDbl; 
double artRate = 2.67, carrRate = 1.49, beetRate = .67;
//double discountDbl;
//double discountRate = 0.05;
decimal totalweightDbl;
//double shiprateDbl = 3.50, shiprate1Dbl = 10.00, shiprate2Dbl = 9.50, shiprate3Dbl = 0.10;
decimal totalshipDbl;
//var shipcostVar;

String outputString;    

//Inputs
artDbl = int.Parse(artBox.Text);
carrDbl = int.Parse(carrBox.Text);
beetDbl = int.Parse(beetBox.Text);

    //Results for weight multiplied by rate per pound
resultInt = artDbl * artRate;
result1Dbl = carrDbl * carrRate;
result2Dbl = beetDbl * beetRate;
totalweightDbl = artDbl + carrDbl + beetDbl;

//shipcostVar = totalweightDbl * .10;
// Results for total weight of all three items
totalresultDbl = resultInt + result1Dbl + result2Dbl;   

//Outputs
outputString = totalresultDbl.ToString("C");
textBox4.Text = totalresultDbl.ToString("C");


if (totalweightDbl <= 5)
{ totalshipDbl = 3.50m; }
else if (totalweightDbl <= 20)
{ totalshipDbl = 10.00m; }


//textBox5.Text = totalshipDbl.ToString("C");

Answer 1

必须为航运公司做同样的事情。以下是满足要求的方式。

用于存储费率的模型。

public class Rate {
    public int weight { get; set; }
    public Nullable<decimal> basePrice { get; set; }
    public Nullable<int> baseWeight { get; set; }
    public Nullable<decimal> unitPrice { get; set; }
    public Nullable<int> unitWeight { get; set; }
}

从那里，集合可用于保存从持久性存储加载的费率的规则。

rates = new List<Rate>();
rates.Add(new Rate { weight = 5, basePrice = 3.50M });
rates.Add(new Rate { weight = 20, basePrice = 10M });
rates.Add(new Rate { weight = int.MaxValue, basePrice = 9.50M, baseWeight = 20, unitPrice = 0.10M, unitWeight = 1 });

以上显示了原始示例中费率的要求。 weight和basePrice应该是自我解释的。正如你所看到的那样，有两种平衡率，重量可达5磅和20磅。如果需要，baseWeight，unitPrice和unitWeight用于计算可变权重的成本。

用于根据总重量和可用费率计算费率的算法

public decimal? CalculateRate(int totalweight, IList<Rate> lookup) {
    decimal? result = null;

    var availableRates = lookup.OrderBy(r => r.weight);

    var rate = availableRates.FirstOrDefault(r => totalweight <= r.weight) ?? availableRates.LastOrDefault();

    if (rate != null) {
        if (rate.baseWeight != null) {

            var baseRate = rate.basePrice;

            var weighDiff = totalweight - rate.baseWeight.GetValueOrDefault();

            var weightDiffUnits = (int)Math.Ceiling((double)weighDiff / (double)rate.unitWeight.GetValueOrDefault());

            var pricePerDiff = rate.unitPrice.GetValueOrDefault();

            var weightDiffRate = weightDiffUnits * pricePerDiff;

            result = baseRate + weightDiffRate;
        } else {
            result = rate.basePrice;
        }
    }

    return result;
}

进行了以下单元测试以验证算法

[TestMethod]
public void When_4_Pounds() {
    //Arrange
    var totalWeight = 4;
    var expected = 3.5M;

    //Act
    var actual = CalculateRate(totalWeight, rates);

    //Assert
    Assert.AreEqual(expected, actual);
}

[TestMethod]
public void When_Ten_Pounds() {
    //Arrange
    var totalWeight = 10;
    var expected = 10M;

    //Act
    var actual = CalculateRate(totalWeight, rates);

    //Assert
    Assert.AreEqual(expected, actual);
}

[TestMethod]
public void When_Thirty_Pounds() {
    //Arrange
    var totalWeight = 30;
    var expected = 10.5M;

    //Act
    var actual = CalculateRate(totalWeight, rates);

    //Assert
    Assert.AreEqual(expected, actual);
}

如果费率更改，则使用新值更新集合。

使用两个＆＃34;平面＆＃34;计算运费。费率和一个可变利率

1 个答案: