nflowers1228
asked on
Splitting Text File Data for Use in Array
I am taking a class and am a real newbie. I am working on a mortgage calculator. I need to allow the user to select the mortgage terms and interest rates (i.e. 7 years @ 5.5%) from a ListBox, grab the values from an array in a text file based on that selection and then calculate the mortgage payment with the term and the rate read as separate properties/variables.
So the first task is to get the values from the text file which reads:
7, 5.35
15, 5.5
30, 5.75
When I run the code below, I just get the values for the first and second "fields" in the first record. How do I move on to the next line?
Private Sub uiArrayValueButton_Click(B
'displays the interest rates from the text file
Dim loanArrayStreamReader As IO.StreamReader
Dim record As String
Dim indexNum
Dim mortgageTerm As String
Dim mortgageTermArray As Integer
Dim array As String
Dim ListBoxIndex As String
Me.uiDisplayLoanTypeLabel.
'determine if text file exists
If IO.File.Exists("loans.txt"
'create a stream reader object by opening the file for input
loanArrayStreamReader = IO.File.OpenText("loans.tx
'process the loop
Do Until loanArrayStreamReader.Peek
'read the record from the file
record = loanArrayStreamReader.Read
'record = loanArrayStreamReader.Read
'display the term of the record
indexNum = record.IndexOf(",")
'mortgageTerm = record.Substring(0, indexNum) displays the mortgage term
mortgageTerm = record.Substring(indexNum + 1) 'displays the mortgage rate
Me.uiDisplayLoanTypeLabel.
Loop
End If
End Sub
The instructor passed on this code which helps me getting the "fields" from the first record, splitting the line at the comma, but again, I'm not sure how to get to the second line. She assumed that the rates were on one line and the terms on another.
Private Sub uiDisplayButton3_Click_1(B
'genevieve's example
Dim loans As String ' file name
Dim loanArrayStreamReader As IO.StreamReader ' stream reader to read the file
Dim splitCharacter As String = ","
Dim strRates As String ' assuming this is for the interest rates.
loans = "C:\Save This Stuff\school\VBAdvanced\In
loanArrayStreamReader = New IO.StreamReader(loans)
strRates = loanArrayStreamReader.Read
'strRates = loanArrayStreamReader.Read
Dim sarrRates() As String = strRates.Split(splitCharac
For i As Integer = 0 To UBound(sarrRates)
'MessageBox.Show(sarrRates
Me.uiArrayType1PaymentLabe
'Me.uiArrayType1PaymentLab
Next
End Sub
any help would be appreciated... I'm sure I'll be just as challenged by trying to assign the value to the index number of the List Box, but if I could get this figured out, it would be a big help.
nancy
So the first task is to get the values from the text file which reads:
7, 5.35
15, 5.5
30, 5.75
When I run the code below, I just get the values for the first and second "fields" in the first record. How do I move on to the next line?
Private Sub uiArrayValueButton_Click(B
'displays the interest rates from the text file
Dim loanArrayStreamReader As IO.StreamReader
Dim record As String
Dim indexNum
Dim mortgageTerm As String
Dim mortgageTermArray As Integer
Dim array As String
Dim ListBoxIndex As String
Me.uiDisplayLoanTypeLabel.
'determine if text file exists
If IO.File.Exists("loans.txt"
'create a stream reader object by opening the file for input
loanArrayStreamReader = IO.File.OpenText("loans.tx
'process the loop
Do Until loanArrayStreamReader.Peek
'read the record from the file
record = loanArrayStreamReader.Read
'record = loanArrayStreamReader.Read
'display the term of the record
indexNum = record.IndexOf(",")
'mortgageTerm = record.Substring(0, indexNum) displays the mortgage term
mortgageTerm = record.Substring(indexNum + 1) 'displays the mortgage rate
Me.uiDisplayLoanTypeLabel.
Loop
End If
End Sub
The instructor passed on this code which helps me getting the "fields" from the first record, splitting the line at the comma, but again, I'm not sure how to get to the second line. She assumed that the rates were on one line and the terms on another.
Private Sub uiDisplayButton3_Click_1(B
'genevieve's example
Dim loans As String ' file name
Dim loanArrayStreamReader As IO.StreamReader ' stream reader to read the file
Dim splitCharacter As String = ","
Dim strRates As String ' assuming this is for the interest rates.
loans = "C:\Save This Stuff\school\VBAdvanced\In
loanArrayStreamReader = New IO.StreamReader(loans)
strRates = loanArrayStreamReader.Read
'strRates = loanArrayStreamReader.Read
Dim sarrRates() As String = strRates.Split(splitCharac
For i As Integer = 0 To UBound(sarrRates)
'MessageBox.Show(sarrRates
Me.uiArrayType1PaymentLabe
'Me.uiArrayType1PaymentLab
Next
End Sub
any help would be appreciated... I'm sure I'll be just as challenged by trying to assign the value to the index number of the List Box, but if I could get this figured out, it would be a big help.
nancy
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ASKER
Thanks for your help. I did find the error and the problem was that I was clicking on the index option item, then clicking on the button. If I just clicked on the button the items displayed 
I did take your advice and chunk up the code on the page. Here is a problem that I’m having general that is somewhat related. I can’t seem to get past this…
Declared the common variables at the top of the page:
Dim MortgageTerm As Double
Dim MortgageAmount As Double
Dim InterestRate As Double
Dim Payment As Double
Created a Calculate Payment function which takes the values from the text fields on the form:
Public Function CalculatePayment()
'calcualtes based on the value entered in the Mortgage Term Field
MortgageAmount = Val(Me.uiMortgageAmountTex
MortgageTerm = Val(Me.uiMortgageTermTextB
InterestRate = Val((Me.uiInterestRateText
Return (-Financial.Pmt((InterestR
End Function
Click on a button and the stuff calculates 
Private Sub uiCalculatePaymentButton_C
'clicking this button calculates the mortgage payment
Dim Payment As Double = CalculatePayment()
Me.uiDisplayPaymentLabel.T
End Sub
--That works fine : -)
But when I try to use the variables again, even to just display them in a text box or label, they won’t display. No matter what I do it turns up as the value is 0. (sorry this is not your code, because I couldn’t get it to work, I tried another avenue)
--
Public Function CaculatePaymentTextFile()
Dim MortgageTerm As Double
Dim MortgageAmount As Double
Dim Payment As Double
Dim InterestRate As String
Dim loans As String ' file name
Dim loanArrayStreamReader As IO.StreamReader ' stream reader to read the file
Dim splitCharacter As String = ","
Dim strRates As String ' interest rates.
Dim strTerms As String ' mortgage term.
loans = "C:\Save This Stuff\school\VBAdvanced\In
loanArrayStreamReader = New IO.StreamReader(loans)
'declare the values of the mortgage terms and interest rate variables
strRates = loanArrayStreamReader.Read
'single dimensional array
strTerms = loanArrayStreamReader.Read
Dim sarrRates() As String = strRates.Split(splitCharac
Dim sarrTerms() As String = strTerms.Split(splitCharac
If Me.uiLoanTypeListBox.Selec
'this just shows me that pulling the values is working :-)
MortgageTerm = sarrTerms(0)
InterestRate = sarrRates(0)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(1)
MortgageTerm = sarrTerms(1)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(2)
MortgageTerm = sarrTerms(2)
End If
Return (-Financial.Pmt((InterestR
End Function
I tried a simpler version to see if I could extract just the Mortgage term and I can’t even do that, it shows up a zero.
Public Function CheckValues()
‘this is commented out because I tried to call the values from the text boxes again and clearly that doesn’t work.
'MortgageAmount = Val(Me.uiMortgageAmountTex
'MortgageTerm = Val(Me.uiMortgageTermTextB
'InterestRate = Val((Me.uiInterestRateText
Dim NumberPayments = MortgageTerm * 12 ‘hoping this would pull MortgageTerm from the values entered before
Return NumberPayments & "help")
End Function
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.TextBox2.Text = CheckValues()
End Sub
I get 0help when I generate this… If this is too lengthy to handle I totally understand. I just want to know how to reuse the variables. I’m probably way off base. Please let me know if I’m hopeless…
THANKS!
I did take your advice and chunk up the code on the page. Here is a problem that I’m having general that is somewhat related. I can’t seem to get past this…
Declared the common variables at the top of the page:
Dim MortgageTerm As Double
Dim MortgageAmount As Double
Dim InterestRate As Double
Dim Payment As Double
Created a Calculate Payment function which takes the values from the text fields on the form:
Public Function CalculatePayment()
'calcualtes based on the value entered in the Mortgage Term Field
MortgageAmount = Val(Me.uiMortgageAmountTex
MortgageTerm = Val(Me.uiMortgageTermTextB
InterestRate = Val((Me.uiInterestRateText
Return (-Financial.Pmt((InterestR
End Function
Click on a button and the stuff calculates 
Private Sub uiCalculatePaymentButton_C
'clicking this button calculates the mortgage payment
Dim Payment As Double = CalculatePayment()
Me.uiDisplayPaymentLabel.T
End Sub
--That works fine : -)
But when I try to use the variables again, even to just display them in a text box or label, they won’t display. No matter what I do it turns up as the value is 0. (sorry this is not your code, because I couldn’t get it to work, I tried another avenue)
--
Public Function CaculatePaymentTextFile()
Dim MortgageTerm As Double
Dim MortgageAmount As Double
Dim Payment As Double
Dim InterestRate As String
Dim loans As String ' file name
Dim loanArrayStreamReader As IO.StreamReader ' stream reader to read the file
Dim splitCharacter As String = ","
Dim strRates As String ' interest rates.
Dim strTerms As String ' mortgage term.
loans = "C:\Save This Stuff\school\VBAdvanced\In
loanArrayStreamReader = New IO.StreamReader(loans)
'declare the values of the mortgage terms and interest rate variables
strRates = loanArrayStreamReader.Read
'single dimensional array
strTerms = loanArrayStreamReader.Read
Dim sarrRates() As String = strRates.Split(splitCharac
Dim sarrTerms() As String = strTerms.Split(splitCharac
If Me.uiLoanTypeListBox.Selec
'this just shows me that pulling the values is working :-)
MortgageTerm = sarrTerms(0)
InterestRate = sarrRates(0)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(1)
MortgageTerm = sarrTerms(1)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(2)
MortgageTerm = sarrTerms(2)
End If
Return (-Financial.Pmt((InterestR
End Function
I tried a simpler version to see if I could extract just the Mortgage term and I can’t even do that, it shows up a zero.
Public Function CheckValues()
‘this is commented out because I tried to call the values from the text boxes again and clearly that doesn’t work.
'MortgageAmount = Val(Me.uiMortgageAmountTex
'MortgageTerm = Val(Me.uiMortgageTermTextB
'InterestRate = Val((Me.uiInterestRateText
Dim NumberPayments = MortgageTerm * 12 ‘hoping this would pull MortgageTerm from the values entered before
Return NumberPayments & "help")
End Function
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Me.TextBox2.Text = CheckValues()
End Sub
I get 0help when I generate this… If this is too lengthy to handle I totally understand. I just want to know how to reuse the variables. I’m probably way off base. Please let me know if I’m hopeless…
THANKS!
ASKER
I got it to work. thanks for your help. I know I didn't use your code directly, but your logic was really helpful. I was better able to understand where i needed to go. I know it's not perfect, but it works :-) Thanks for all your help and encouragement... looking forward to more programming.
Public Class MortgageCalculatorForm
Dim MortgageTerm As Double
Dim MortgageAmount As Double
Dim Payment As Double
Dim InterestRate As Double
Private Sub MortgageCalculatorForm_Loa
'declares INITIAL Amounts for data entry fields on the screen
Me.uiMortgageAmountTextBox
Me.uiDisplayPaymentLabel.T
Me.uiAmortTableRichTextBox
Me.uiMortgageAmountTextBox
Me.uiLoanTypeListBox.Selec
End Sub
Private Sub uiCalculatePaymentButton_C
'clicking this button calculates the mortgage payment
'Dim Payment As Double
If Me.uiMortgageTermTextBox.T
Payment = CalculatePayment()
Else
Payment = CaculatePaymentTextFile()
End If
Me.uiDisplayPaymentLabel.T
Me.uiAmortTableRichTextBox
End Sub
Private Sub uiAmortTableRichTextBox_Ke
'based on Douglass Cole's suggestion and code snippet. Thanks Douglass :-)
'Suppress the keypress in textbox without disabling the textbox
e.Handled = True
End Sub
Private Sub uiAmortTableRichTextBox2_K
'based on Douglass Cole's suggestion and code snippet. Thanks Douglass :-)
'Suppress the keypress in textbox without disabling the textbox
e.Handled = True
End Sub
Public Function CalculatePayment()
Dim MortgageTerm As Double
Dim MortgageAmount As Double
'Dim Payment As Double
Dim InterestRate As Double
MortgageAmount = Val(Me.uiMortgageAmountTex
MortgageTerm = Val(Me.uiMortgageTermTextB
InterestRate = Val(Me.uiInterestRateTextB
Return (MortgageAmount * (InterestRate) / (1 - Math.Pow(1 + (InterestRate), -(MortgageTerm))))
End Function
Private Function CaculatePaymentTextFile()
Dim loans As String ' file name
Dim loanArrayStreamReader As IO.StreamReader ' stream reader to read the file
Dim splitCharacter As String = ","
Dim strRates As String ' interest rates.
Dim strTerms As String ' mortgage term.
MortgageAmount = Val(Me.uiMortgageAmountTex
loans = "C:\loans.txt"
loanArrayStreamReader = New IO.StreamReader(loans)
'declare the values of the mortgage terms and interest rate variables
strRates = loanArrayStreamReader.Read
'single dimensional array
strTerms = loanArrayStreamReader.Read
Dim sarrRates() As String = strRates.Split(splitCharac
Dim sarrTerms() As String = strTerms.Split(splitCharac
If Me.uiLoanTypeListBox.Selec
'this just shows me that pulling the values is working :-)
MortgageTerm = sarrTerms(0)
InterestRate = sarrRates(0)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(1)
MortgageTerm = sarrTerms(1)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(2)
MortgageTerm = sarrTerms(2)
End If
Return (MortgageAmount * (InterestRate / 100) / 12) / (1 - Math.Pow(1 + (InterestRate / 100) / 12, -(MortgageTerm * 12)))
End Function
End Class
Public Class MortgageCalculatorForm
Dim MortgageTerm As Double
Dim MortgageAmount As Double
Dim Payment As Double
Dim InterestRate As Double
Private Sub MortgageCalculatorForm_Loa
'declares INITIAL Amounts for data entry fields on the screen
Me.uiMortgageAmountTextBox
Me.uiDisplayPaymentLabel.T
Me.uiAmortTableRichTextBox
Me.uiMortgageAmountTextBox
Me.uiLoanTypeListBox.Selec
End Sub
Private Sub uiCalculatePaymentButton_C
'clicking this button calculates the mortgage payment
'Dim Payment As Double
If Me.uiMortgageTermTextBox.T
Payment = CalculatePayment()
Else
Payment = CaculatePaymentTextFile()
End If
Me.uiDisplayPaymentLabel.T
Me.uiAmortTableRichTextBox
End Sub
Private Sub uiAmortTableRichTextBox_Ke
'based on Douglass Cole's suggestion and code snippet. Thanks Douglass :-)
'Suppress the keypress in textbox without disabling the textbox
e.Handled = True
End Sub
Private Sub uiAmortTableRichTextBox2_K
'based on Douglass Cole's suggestion and code snippet. Thanks Douglass :-)
'Suppress the keypress in textbox without disabling the textbox
e.Handled = True
End Sub
Public Function CalculatePayment()
Dim MortgageTerm As Double
Dim MortgageAmount As Double
'Dim Payment As Double
Dim InterestRate As Double
MortgageAmount = Val(Me.uiMortgageAmountTex
MortgageTerm = Val(Me.uiMortgageTermTextB
InterestRate = Val(Me.uiInterestRateTextB
Return (MortgageAmount * (InterestRate) / (1 - Math.Pow(1 + (InterestRate), -(MortgageTerm))))
End Function
Private Function CaculatePaymentTextFile()
Dim loans As String ' file name
Dim loanArrayStreamReader As IO.StreamReader ' stream reader to read the file
Dim splitCharacter As String = ","
Dim strRates As String ' interest rates.
Dim strTerms As String ' mortgage term.
MortgageAmount = Val(Me.uiMortgageAmountTex
loans = "C:\loans.txt"
loanArrayStreamReader = New IO.StreamReader(loans)
'declare the values of the mortgage terms and interest rate variables
strRates = loanArrayStreamReader.Read
'single dimensional array
strTerms = loanArrayStreamReader.Read
Dim sarrRates() As String = strRates.Split(splitCharac
Dim sarrTerms() As String = strTerms.Split(splitCharac
If Me.uiLoanTypeListBox.Selec
'this just shows me that pulling the values is working :-)
MortgageTerm = sarrTerms(0)
InterestRate = sarrRates(0)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(1)
MortgageTerm = sarrTerms(1)
ElseIf Me.uiLoanTypeListBox.Selec
InterestRate = sarrRates(2)
MortgageTerm = sarrTerms(2)
End If
Return (MortgageAmount * (InterestRate / 100) / 12) / (1 - Math.Pow(1 + (InterestRate / 100) / 12, -(MortgageTerm * 12)))
End Function
End Class
Hi , Only just got round to checking on this...
I notice in your version that works you have commented the
Dim Payment as Double Line
This is the killer and is what is known as Variable Scoping; it is the scope at which the variable is defined....
Because at the top you have Dimmed Payment once, that variable is accesible to every method(sub/function) within that Class(form) but because VB.Net is what is known as 'Strongly Typed' there is nothing to stop you from defining a Variable within a Method even of the same name (in the good old days VB6 would complain, vigourously about this).
As far as .Net is concerned because you have defined it *within* that method (ie the 'scope' of the variable is Local not Global to that method) whenever, within that method you refer to Payment it thinks you mean the Payment variable within that method. If within that method you did want *another* variable of the same name as the global defined one to set the Form-Scope variable value instead you have to tell it where it is by using
Me.Payment = 2323
otherwise just
Payment=2323
sets the Payment variable that you have explicity created with the CreatePayment Function
Funnily enough the best way to do things is not always with wide scope varaibles anyway, it is usually better to go down the OO route, heres an example
Public Class MortgageCalculator
Public MortgageTerm As Double
Public MortgageAmount As Double
Public InterestRate As Double
Public Overloads Function CalculatePayment()
Return (MortgageAmount * (InterestRate) / (1 - Math.Pow(1 + (InterestRate), -(MortgageTerm))))
End Function
Public Overloads Function CalculatePayment(ByVal nMortgageAmount As Double, ByVal nMortgageTerm As Double, ByVal nPayment As Double, ByVal nInterestRate As Double) As Double
MortgageAmount = Val(nMortgageAmount)
MortgageTerm = Val(nMortgageTerm)
InterestRate = Val(nInterestRate)
Return CalculatePayment
End Function
End Class
Now very roughly ( i havenet got the right formulas and numbers here ,i know) at the top of your Form you can
Dim myMortgageCalculator as new MortgageCalculator
And then when you want to calculate a result all you have to do is either
myMortgageCalculator.Mortg
myMortgageCalculator.Inter
myMortgageCalculator.Mortg
ResultTextBox.Text = myMortgageCalculator.Calcu
or (and the or is because the Same Function has two different Parameter Sets) even better
ResultTextBox.Text = myMortgageCalculator.Calcu
This is *the* way to do it, it also helps to group the Variables and realted functions together and out of the way of the Form Code and improves readability and reusability. Obviously within that Mortgage Calculator Class you couls/should move the logic for reading the File in too, so all that your form needs to know how to do is query a MortgageCalculator Object...
It maybe worth a couple of hours of your time in the MSDN and read a little about Variable Scoping,Overloading. Namespaces and Instantiating Objects. In fact i spend much of my time in the MSDN - its just not possible for a human to know everything that there is to know about .NET
'F1' is your friend!!!
Thanks for the points BTW :-) You are my officially my first 'EE Customer', glad to be of help... and i hope this comment hasnt furhter confused you..
I notice in your version that works you have commented the
Dim Payment as Double Line
This is the killer and is what is known as Variable Scoping; it is the scope at which the variable is defined....
Because at the top you have Dimmed Payment once, that variable is accesible to every method(sub/function) within that Class(form) but because VB.Net is what is known as 'Strongly Typed' there is nothing to stop you from defining a Variable within a Method even of the same name (in the good old days VB6 would complain, vigourously about this).
As far as .Net is concerned because you have defined it *within* that method (ie the 'scope' of the variable is Local not Global to that method) whenever, within that method you refer to Payment it thinks you mean the Payment variable within that method. If within that method you did want *another* variable of the same name as the global defined one to set the Form-Scope variable value instead you have to tell it where it is by using
Me.Payment = 2323
otherwise just
Payment=2323
sets the Payment variable that you have explicity created with the CreatePayment Function
Funnily enough the best way to do things is not always with wide scope varaibles anyway, it is usually better to go down the OO route, heres an example
Public Class MortgageCalculator
Public MortgageTerm As Double
Public MortgageAmount As Double
Public InterestRate As Double
Public Overloads Function CalculatePayment()
Return (MortgageAmount * (InterestRate) / (1 - Math.Pow(1 + (InterestRate), -(MortgageTerm))))
End Function
Public Overloads Function CalculatePayment(ByVal nMortgageAmount As Double, ByVal nMortgageTerm As Double, ByVal nPayment As Double, ByVal nInterestRate As Double) As Double
MortgageAmount = Val(nMortgageAmount)
MortgageTerm = Val(nMortgageTerm)
InterestRate = Val(nInterestRate)
Return CalculatePayment
End Function
End Class
Now very roughly ( i havenet got the right formulas and numbers here ,i know) at the top of your Form you can
Dim myMortgageCalculator as new MortgageCalculator
And then when you want to calculate a result all you have to do is either
myMortgageCalculator.Mortg
myMortgageCalculator.Inter
myMortgageCalculator.Mortg
ResultTextBox.Text = myMortgageCalculator.Calcu
or (and the or is because the Same Function has two different Parameter Sets) even better
ResultTextBox.Text = myMortgageCalculator.Calcu
This is *the* way to do it, it also helps to group the Variables and realted functions together and out of the way of the Form Code and improves readability and reusability. Obviously within that Mortgage Calculator Class you couls/should move the logic for reading the File in too, so all that your form needs to know how to do is query a MortgageCalculator Object...
It maybe worth a couple of hours of your time in the MSDN and read a little about Variable Scoping,Overloading. Namespaces and Instantiating Objects. In fact i spend much of my time in the MSDN - its just not possible for a human to know everything that there is to know about .NET
'F1' is your friend!!!
Thanks for the points BTW :-) You are my officially my first 'EE Customer', glad to be of help... and i hope this comment hasnt furhter confused you..
ASKER
Thanks. This was really helpful. I'm still working on the classes (I posted an entirely different thread for that one :-) I was able to get the classes working for the first iteration of this project, but when I started combining the two, I had a lot of trouble. I know it will just take time and practice....
ASKER
Thanks again for your help.