Visual Basic関数の変数宣言でエラーが発生しました

Question

Visual Basic関数で問題が発生しました。私は私のエラーは、関数の宣言変数のどこかにあると思うが、私は完全にはわからない。プログラムは、病院で過ごした日数を私が宣言した定数= 350で乗算し、その数に雑多な料金を加えたものですが、私は0を返します。

のVisual Basicコード：

Const decStay_Rate As Decimal = 350 

    Private decLength As Integer 
    Private decMedication As Decimal 
    Private decSurgical As Decimal 
    Private decLab As Decimal 
    Private decPhysical As Decimal 
    Private decTotalStayPrice As Decimal 
    Private decTotalMiscCharges As Decimal 

    Private decTotal As Decimal 
    Dim decStay As Decimal 


    Function validateInputField() As Boolean 
     If Not Decimal.TryParse(txtLength.Text, decLength) Then 
      MessageBox.Show("Stay Length must be numeric") 
     End If 
     If Not Decimal.TryParse(txtMedication.Text, decMedication) Then 
      MessageBox.Show("Medication cost must be numeric") 
     End If 
     If Not Decimal.TryParse(txtSurgical.Text, decSurgical) Then 
      MessageBox.Show("Surgical cost must be numeric") 
     End If 
     If Not Decimal.TryParse(txtLabFees.Text, decLab) Then 
      MessageBox.Show("Lab fees must be numeric") 
     End If 
     If Not Decimal.TryParse(txtPhysicalRehab.Text, decPhysical) Then 
      MessageBox.Show("Physical Rehab cost must be numeric") 
     End If 

     Return True 
    End Function 

    Function CalcStayCharges(ByVal decLength As Decimal) As Decimal 
     Dim decTotalStayPrice As Decimal 
     decTotalStayPrice = decLength * decStay_Rate 
     Return decTotalStayPrice 
    End Function 

    Function CalcMiscCharges(ByVal decmedication As Decimal, ByVal decsurgical As Decimal, ByVal decLab As Decimal, ByVal decPhysical As Decimal) As Decimal 
     Dim decTotalMiscCharges As Decimal 
     decTotalMiscCharges = decmedication + decsurgical + decLab + decPhysical 
     Return decTotalMiscCharges 
    End Function 

    Private Function CalcTotalCharges(ByVal decTotalStayPrice As Decimal, ByVal decTotalMiscCharges As Decimal) As Decimal 
     Dim decTotalCharge As Decimal 
     decTotalCharge = decTotalStayPrice + decTotalMiscCharges 
     Return decTotalCharge 
    End Function 
    Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click 

     txtLabFees.Text = String.Empty 
     txtLength.Text = String.Empty 
     txtMedication.Text = String.Empty 
     txtPhysicalRehab.Text = String.Empty 
     txtSurgical.Text = String.Empty 

    End Sub 

    Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click 
     Me.Close() 
    End Sub 

    Private Sub btnCalc_Click(sender As Object, e As EventArgs) Handles btnCalc.Click 
     Dim decTotal As Decimal 

     lblOutput.Text = String.Empty 
     If validateInputField() Then 
      decTotal = CalcTotalCharges(decTotalStayPrice, decTotalMiscCharges) 

      lblOutput.Text = decTotal.ToString("c") 
     End If 
    End Sub 

おかげで、 エリック

Answer 1

それが数値かどうかをチェックするDecimal.TryParse(txtLength.Text, decLength)を必要としないすべての最初の。 IsNumericだからIsNumeric(txtLength.Text)を使うことができます。 Decimal.TryParseは、txtLength.TextからdecLengthに値を割り当てますが、成功した場合はこの場合に行う必要はありません。

私はに方法validateInputFieldを変更します：あなたは、その後に正しい値を渡したいと思うだろう

Private decLength As Integer 
Private decMedication As Decimal 
Private decSurgical As Decimal 
Private decLab As Decimal 
Private decPhysical As Decimal 
Private decTotalStayPrice As Decimal 
Private decTotalMiscCharges As Decimal 

Private decTotal As Decimal 
Dim decStay As Decimal 

：彼らはあなたの混乱を引き起こしているように私はこれらのすべてを削除したい

Function validateInputField() As Boolean 
    If Not IsNumeric(txtLength.Text) Then 
     MessageBox.Show("Stay Length must be numeric") 
     Return False 
    End If 
    If Not IsNumeric(txtMedication.Text) Then 
     MessageBox.Show("Medication cost must be numeric") 
     Return False 
    End If 
    If Not IsNumeric(txtSurgical.Text) Then 
     MessageBox.Show("Surgical cost must be numeric") 
     Return False 
    End If 
    If Not IsNumeric(txtLabFees.Text) Then 
     MessageBox.Show("Lab fees must be numeric") 
     Return False 
    End If 
    If Not IsNumeric(txtPhysicalRehab.Text) Then 
     MessageBox.Show("Physical Rehab cost must be numeric") 
     Return False 
    End If 

    Return True 
End Function 

方法CalcTotalCharges：

decTotal = CalcTotalCharges(value1, value2) 

ラウンドアバウト方式でおそらく後：

Private Sub btnCalc_Click(sender As Object, e As EventArgs) Handles btnCalc.Click 
    Dim decTotal As Decimal 

    lblOutput.Text = "" 
    If validateInputField() Then 
     decTotal = CalcTotalCharges(CalcStayCharges(CDec(txtLength.Text)), CalcMiscCharges(CDec(txtMedication.Text), CDec(txtSurgical.Text), CDec(txtLabFees.Text), CDec(txtPhysicalRehab.Text))) 

     lblOutput.Text = decTotal.ToString("c") 
    End If 
End Sub