2012-10-17 91 views
0

我想弄清楚如何完成这个程序,并获得计算显示在文本框中。这是我到目前为止的基本代码将采购价格和赎回率并计算折扣和利率。不知道我在做什么错误。vb.net折扣和利率计划

Option Strict On 

Public Class _Default 
    Inherits System.Web.UI.Page 

    Dim Purchase As Double 
    Dim Redemption As Double 
    Dim DiscountRate As Double 
    Dim InterestRate As Double 

    Protected Sub btnCalculate_Click(sender As Object, e As EventArgs) _ 
              Handles btnCalculate.Click 

     Double.TryParse(txtPurchase.Text, Purchase) 
     Double.TryParse(txtRedemption.Text, Redemption) 
     Double.TryParse(txtDiscount.Text, DiscountRate) 
     Double.TryParse(txtInterest.Text, InterestRate) 

     If (CDbl(txtPurchase.Text) <= 0) Then 
      MsgBox("Please enter an amount greater than 0") 

     End If 

     If (CDbl(txtRedemption.Text) <= 0) Then 
      MsgBox("Please enter an amount greater than 0") 
     End If 

     DiscountRate = Purchase - Redemption/Purchase 
     InterestRate = Purchase - Redemption/Redemption 

    End Sub 
End Class 
+0

你能解释一下这个问题? –

+0

@JohnWoo试图创建一个计算债券折扣和利率的网络程序。公式正好在购买 - 赎回除以购买和其他方式,但他们没有显示出来 – compucrazy

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当你在调试器中单步执行时,'DiscountRate'和'InterestRate'在方法的最后得到正确计算? – yhw42

回答

0

当你解析它们时,它们的变量不会自动绑定到控件上。看起来你只需要您的计算后补充一点:

txtDiscount.Text = DiscountRate 
txtInterest.Text = InterestRate 
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工作!谢谢! – compucrazy

1

它看起来像您有Operator Precedence一个问题,你需要一些支架。您在第一种情况下通过购买划分您的赎回,然后从购买中扣除。在第二种情况下,您将通过兑换进行赎回,并从购买中扣除1的结果。尝试这个。您还需要将结果分配给所显示的控件。

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或者更简单地说

txtDiscount.Text = ((Purchase - Redemption)/Purchase).ToString 
txtInterest.Text = ((Purchase - Redemption)/Redemption).ToString