私はVB.netを学んでいます。MS VB.net を使用して、Brian Siler の特別版 (2001 年) の第 3 章に従っています。VB ではあまり変わっていないように見えますが、ツールボックスからテーブルを追加する際に問題が発生しました。
ツールボックス (Visual Studio 2012 Express のバージョン、ASP.net 2012) には、VB.net プロジェクトをビルドするために、TextBox や Table などの項目があります。Web アプリを構築するために、TextBox、Label などを追加して問題なくコーディングできます。ただし、テーブルを追加すると問題が発生します。
Textbox と Label と同様に、tblAmortize最初にテーブル ID の名前を ( に ) 変更します。次に、彼らの本からコードを入力すると、エラーが発生しました。
'tblAmortize' is not declared. It may be inaccessible due to its protection level"
私が知っているように、 TextBox アイテムなどは、txtPrincipal.Text使用するときに宣言する必要はありません。しかし、この「テーブル」tblAmortizeアイテムは最初に宣言する必要があるtblAmortizeようです。完全なコードは次のとおりです。Form 2btnShowDetail_ClickForm 1
Public Class Hello_Web
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim intTerm As Integer 'Term, in years
Dim decPrincipal As Decimal 'Principal amount $
Dim decIntRate As Decimal 'Interst rate %
Dim dblPayment As Double 'Monthly payment $
Dim decMonthInterest As Decimal 'Interest part of monthly payment
Dim decTotalInterest As Decimal = 0 'Total interest paid
Dim decMonthPrincipal As Decimal 'Principal part of monthly pament
Dim decTotalPrincipal As Decimal = 0 'Remaining principal
Dim intMonth As Integer 'Current month
Dim intNumPayments As Integer 'Number of monthly payments
Dim i As Integer 'Temporary loop counter
Dim rowTemp As TableRow 'Temporary row object
Dim celTemp As TableCell 'Temporary cell object
If Not IsPostBack Then 'Evals true first time browser hits the page
'SET Up THE TABLE HEADER ROW
rowTemp = New TableRow()
For i = 0 To 4
celTemp = New TableCell()
rowTemp.Cells.Add(celTemp)
celTemp = Nothing
Next
rowTemp.Cells(0).Text = "Payment"
rowTemp.Cells(1).Text = "Interest"
rowTemp.Cells(2).Text = "Principal"
rowTemp.Cells(3).Text = "Total Int."
rowTemp.Cells(4).Text = "Balance"
rowTemp.Font.Bold = True
tblAmortize.Rows.Add(rowTemp)
'PULL VALUES FROM SESSION VARIABLES
intTerm = Convert.ToInt32(Session("term"))
decPrincipal = Convert.ToDecimal(Session("Principal"))
decIntRate = Convert.ToDecimal(Session("IntRate"))
dblPayment = Convert.ToDecimal(Session("decPayment"))
'CALCULATE AMORTIZATION SCHEDULE
intNumPayments = intTerm * 12
decTotalPrincipal = decPrincipal
For intMonth = 1 To intNumPayments
'Determine Values For the Current Row
decMonthInterest = (decIntRate / 100) / 12 * decTotalPrincipal
decTotalInterest = decTotalInterest + decMonthInterest
decMonthPrincipal = Convert.ToDecimal(dblPayment) - decMonthInterest
If decMonthPrincipal > decPrincipal Then
decMonthPrincipal = decPrincipal
End If
decTotalPrincipal = decTotalPrincipal - decMonthPrincipal
'Add the values to the table
rowTemp = New TableRow()
For i = 0 To 4
celTemp = New TableCell()
rowTemp.Cells.Add(celTemp)
celTemp = Nothing
Next i
rowTemp.Cells(0).Text = intMonth.ToString
rowTemp.Cells(1).Text = Format(decMonthInterest, "$###0.00")
rowTemp.Cells(2).Text = Format(decMonthPrincipal, "$###0.00")
rowTemp.Cells(3).Text = Format(decTotalInterest, "$###0.00")
rowTemp.Cells(4).Text = Format(decTotalPrincipal, "$###0.00")
tblAmortize.Rows.Add(rowTemp)
rowTemp = Nothing
'PrevFormat()
Next intMonth
End If
End Sub
Protected Sub btnCalculate_Click(sender As Object, e As EventArgs) Handles btnCalculate.Click
Dim decPrincipal As Decimal
Dim decIntRate As Decimal
Dim intTerm As Integer, dblPayment As Double
'Store the principle in the variable decprincipal
'decPrincipal = CDbl(txtPrincipal.Text)
decPrincipal = (txtPrincipal.Text)
'Convert interest rate to its decimal equivalent
' i.e. 12.75 becomes 0.1275
decIntRate = CDbl(txtIntrate.Text) / 100
'Convert annual interest rate to monthly
' by dividing by 12 (months in a year)
decIntRate = decIntRate / 12
'Convert number of years to number of months
' by multiplying by 12 (months in a year)
intTerm = CDbl(txtTerm.Text) * 12
'Calculate and display the monthly payment.
' The format function makes the displayed number look good.
dblPayment = decPrincipal * (decIntRate / (1 - (1 + decIntRate) ^ -intTerm))
txtPayment.Text = Format(dblPayment, "$#,##0.00")
'Add Amortization Schedule
' The Schedule button will be shown only after you click the Calculate Payment LinkButton
btnShowDetail.Visible = True
End Sub
Protected Sub btnShowDetail_Click(sender As Object, e As EventArgs) Handles btnShowDetail.Click
'Storetext box values in session variables
Session.Add("Principal", txtPrincipal.Text)
Session.Add("IntRate", txtIntrate.Text)
Session.Add("Term", txtTerm.Text)
Session.Add("Payment", txtPayment.Text)
'Display the Amortization form
Response.Redirect("frmAmort.aspx")
End Sub
End Class