how to increment elements in an array

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  15 years ago

  by D Ashcroft

  dan ashcroft

  Cirencester / San Juan, Puerto Rico

  Joined 15 years ago

  I am working on an exercise from the Deitel "Simply" Visual Basic book. p.379. Here is the objective :
  to create an application that determines how many salespeople earned salaries in each range (the reanges are 0-99, 100-199, 200-299 etc).
  
  create a string array and initialize it to contain the salary ranges
  
  create an array that represents the number of salaries in each range. this is a decimal array to store_the number of employees who earn salaries in each range.
  
  create an event handlers for a calculate button: obtain user input from an Enter Sales Text Box.
  
  calculate the commission due and add to the base salary.
  
  Increment the element in array decSalaries that corresponds to the the employees salary in the Total Salary : label
  
  if you would please take a look at the code I have so far written this morning, you will see that (I think) I have achieved most of the objectives. I am able to calculate the
  commission due and display it correctly.
  
  
  
  
  
  
  
  
  
  
  
  
  
  

  Public Class FrmSalarySurvey
     Inherits System.Windows.Forms.Form
  
     'string array stores the salary ranges
     Dim m_strSalaryRanges As String() = New String() _
     {"200 - 299", "300 - 399", "400 - 499", "500 - 599", "600 - 699", "700 - 799", _
     "800 - 899", "900 - 999", "1000 - "}
  
     'an empty array to store how many employees earn each salary range
     Dim m_decSalaries As Decimal() = New Decimal(m_strSalaryRanges.GetUpperBound(0)) {}
  
     Dim m_intCounter As Integer = 1 ' number of salaries
  
  Private Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
        Dim dblgrossSales As Double
        Dim dblcommission As Double = 0.09
        Dim dblSalary As Double
        Dim dblBaseSalary As Double = 200
  
        dblgrossSales = Val(txtInputSales.Text) ' assigning a property's value to a variable
  
        dblSalary = dblgrossSales * dblcommission + dblBaseSalary 'calculate the total salary due
  
        lblTotalSalary.Text = Convert.ToString(dblSalary) 'returning the variable to a property as a String
  
        'increment the element in m_decSalaries array that corresponds to the employee's salary range
  
        m_intCounter += 1 
  End Sub
  End Class ' FrmSalarySurvey
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

  My problem is now this : how to "increment the element in array decSalaries that correspond to the employee's saalary range"
  I am supposed to create a loop , I heard yesterday from a friend who wont tell me anymore !
  

   

  Thanks for any tips.

  Dan Ashcroft.
  
  
  
  

   

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  15 years ago

  by computerg33k

  Dana Marie Dillman

  Somewhere over the Rainbow, United States

  Joined 16 years ago

   m_intCounter += 1  ' This is your incrementer

   

  At the beginning of your code you'll need a for loop and after the above line you need to end the for loop.

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  15 years ago

  by jmcilhinney

  John McIlhinney

  Sydney, Australia

  Joined 15 years ago
  You then need to calculate each persons salary range and then increment the corresponding array element.  To do this you need the index of that array element.  To find that you determine the index in the salary range array using Array.IndexOf.
  
  
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  15 years ago

  by D Ashcroft

  dan ashcroft

  Cirencester / San Juan, Puerto Rico

  Joined 15 years ago

  in order to "increment the element in array decSalaries that corresponds to the employees salary range" , am I on the right track doing this ?
   'string array stores the salary ranges
     Dim mstrSalaryRanges As String() = New String() _
     {"200 - 299", "300 - 399", "400 - 499", "500 - 599", "600 - 699", "700 - 799"}
  
   'an empty array to store how many employees earn each salary range
     Dim mdecSalaries As Decimal() = New Decimal(mstrSalaryRanges.GetUpperBound(0)) {}
  
    Private Sub btnCalculateClick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
        Dim dblgrossSales As Double
        Dim dblcommission As Double = 0.09
        Dim dblSalary As Double
        Dim dblBaseSalary As Double = 200
  
        dblgrossSales = Val(txtInputSales.Text)
  
        dblSalary = dblgrossSales * dblcommission + dblBaseSalary
  
        lblTotalSalary.Text = Convert.ToString(dblSalary) 
  
  increment the element in mdecSalaries array that corresponds to the
        'employee's salary range
        Select Case dblSalary
           Case 200 To 299
              mdecSalaries(0) += 1
           Case 300 To 399
              mdecSalaries(1) += 1
           Case 400 To 499
              mdecSalaries(2) += 1
           Case 500 To 599
              mdecSalaries(3) += 1
           Case 600 To 699
              mdecSalaries(4) += 1
           Case 700 To 799
              m_decSalaries(5) += 1
   End Select
  
  I get the feeling that I am going about this the long way round.
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

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  15 years ago

  by D Ashcroft

  dan ashcroft

  Cirencester / San Juan, Puerto Rico

  Joined 15 years ago
  Dim i As Integer
        For i = 0 To 6
           Dim m_Str As String
  
           m_Str = Convert.ToString(m_decSalaries(i))
  
           lstSalaryTotals.Items.Add(m_strSalaryRanges(i) + ControlChars.Tab & m_Str)
  
  was what I was missing, in order to display the incremented elements.
  
  
  
  
  
  
  
  
  
  
  
  
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