因此,考虑到期限和利率,我试图制定一个程序来计算每个月需要保存的金额以累积特定金额。但是它的数量是错误的,我不知道为什么。例如,当给定期望的累计金额为40,000,期限为20年,利率为6%时,它应该以每月86.57美元的价格出售,而是给出一些其他金额。任何帮助将不胜感激。
Option Explicit On
Option Strict On
Option Infer Off
Public Class frmMain
Private Sub btnExit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnExit.Click
Me.Close()
End Sub
Private Sub ClearSavings(ByVal sender As Object, ByVal e As System.EventArgs) _
Handles txtFuture.TextChanged, txtTerm.TextChanged, txtRate.TextChanged
lblSave.Text = String.Empty
End Sub
Private Sub btnCalc_Click(sender As Object, e As EventArgs) Handles btnCalc.Click
Dim dblFuture As Double
Dim dblTerm As Double
Dim dblRate As Double
Dim dblSave As Double
Double.TryParse(txtFuture.Text, dblFuture)
Double.TryParse(txtTerm.Text, dblTerm)
Double.TryParse(txtRate.Text, dblRate)
'Convert to decimal
If dblRate >= 1 Then
dblRate = dblRate / 100
End If
'calculate the savings per month
dblSave = -Financial.Pmt(dblRate, dblTerm, 0, dblFuture)
lblSave.Text = dblSave.ToString("C2")
End Sub
结束班