在Visual Basic中读取文件

Question

I'm working on a program and am supposed to follow this set of directions:

1. Create a class with the following (This may or may not be done correctly, I'm not sure)
     Attributes
        strName As String
        dblSalary As Double
     Properties
       name- can be any string
       salary- can only be positive numbers, if the number is negative, set it to equal 10
     computeSalary(intMonths As Integer)
        When called, the salary * number of months is returned.
2. Read in a file selected by the user. (I think I have this part done correctly)
     Must be a txt file
     Filter open file dialog to only show txt files
3. Once the file is read in, the following menu items are available 
     Show Employee Names
         Another form pops up displaying all the employee names read from the file in  a listbox
     Show Employee Salaries
         Another form pops up displaying all the employee salaries read from the file in a listbox
     Show an Employee
         Another form pops up displaying all the employees names read from the file in a listbox
         When a name is selected from the listbox, labels are filled showing that employees' name and salary.
         In this form there's an option to calculate an employees' salary for a given number of months
             When this button is pushed, an input pop up is shown and the user is asked to enter the number of months for which they'd like the salary to be calculated and displays the salary for the given number of months. 
                For example, if an employee makes $1,000 per month and the user enters a 3, $3,000 would be displayed. 

I have a fairly decent portion of the code written so far and it works correctly for what is written (as far as I can tell anyway). The open file dialog only shows text files, when I select a file the correct menu options are un-greyed out (yes I know that's not a word ha), and clicking each of those menu items takes me to their corresponding forms. So I'm hoping that everything else will fall into place when I get this question answered.

The problem I'm having is reading in the file in such a way that only the names or only the salaries will be displayed in the correct listbox. I'd like to do this in the simplest way possible without having to change a big chunk of my current code if that's at all possible.

Here's what I have so far:

Option Strict On
Imports System.IO

Public Class Main

    Private Sub open_Click(sender As Object, e As EventArgs) Handles open.Click
        Dim open As New OpenFileDialog
        open.Filter = "text files |*.txt|All Files|*.*"
        open.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory)

        If open.ShowDialog() = Windows.Forms.DialogResult.OK Then
            Dim selectedFileName As String = System.IO.Path.GetFileName(open.FileName)
            showNames.Enabled = True
            showSalaries.Enabled = True
            showEmployee.Enabled = True
        End If

        Dim line As String
        Using reader As New StreamReader(open.OpenFile)
            While Not reader.EndOfStream
                line = reader.ReadLine
                Console.WriteLine(line)
            End While
        End Using

    End Sub

    Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ExitToolStripMenuItem.Click
        Me.Close()
        Names.Close()
        Salaries.Close()
        frmTotal.Close()
    End Sub

    Private Sub showNames_Click(sender As Object, e As EventArgs) Handles showNames.Click
        Names.Show()
    End Sub

    Private Sub showSalaries_Click(sender As Object, e As EventArgs) Handles showSalaries.Click
        Salaries.Show()
    End Sub

    Private Sub showEmployee_Click(sender As Object, e As EventArgs) Handles showEmployee.Click
        frmTotal.Show()
    End Sub
End Class

Public Class Project9

    Dim strName As String
    Dim dblSalary As Double

    Private Property Name() As String
        Get
            Return strName
        End Get
        Set(value As String)
            strName = value
        End Set
    End Property

    Private Property Salary() As Double
        Get
            Return dblSalary
        End Get
        Set(value As Double)
            If dblSalary < 0 Then
                dblSalary = 10
            End If
            dblSalary = value
        End Set

    End Property

    Private Function computeSalary(intMonths As Integer) As Double
        Dim dblTotal As Double = dblSalary * intMonths

        Return dblTotal
    End Function

End Class

Here's my text file

Steve McGarret  
1500.00
Danny Williams 
1300.00
Matthew Casey
1700.00
Kelly Severide
1750.00

Any help would be greatly appreciated, also if you notice anything wrong pertaining to the classes, attributes, properties, or function please let me know, I've never worked with any of those before so am not sure that I have it done properly.

Answer 1

Class can be the 'masters' of the data they manage. As such, whatever Salaries.Show and Names.Show are (and whereever they are), these can be internalized to the Project9 class. you almost certainly want the properties Public so you can access them.

One tip, as of VS2012, you no longer need to declare simple props that way:

Public Property Name As String
Public Property Salary as Decimal       ' money almost always should be Decimal

The backing fields (eg strName) are no longer needed as VS creates a _Name variable for you. When you have something like the salary qualification, then you need the full/non auto prop declarations. The computeSalary function is also private so you cant call it externally.

You can (should) also add a constructor to fill in the needed values when you create a new instance (avoids having to set the name and salary each time individually):

Public Sub New(n As String, s As Decimal)
     strName = n
     Salary = s      ' use the code in the prop setter
End Sub

There is nothing in your code for reading the text file (we dont know its layout) nor for posting to the listbox, but here is a tip:

Public Overrides Function ToString() As String
     Return strName &  "   "   & decSalary.ToString
End Sub

Add that function to the Project9 class and modify it to return whatever you need. That way, to populate the listbox, you just add a Project9 instance to it:

 Dim emp As New Project9("Beth", 1000)       ' bad name
 ' creates an emp with the name and salary
 ListBox.Items.Add(emp)

the listbox will use the ToString function for display/ To show just the Names or Salaries, use those Props

EDIT

    Dim newName As String
    Dim newSal As string
    Dim emp As Project9      ' which is crying out for a new name
    Using reader As New StreamReader(open.OpenFile)
        While Not reader.EndOfStream
            newName = reader.ReadLine
            newSal = reader.ReadLine

            emp = New Project9(newName, convert.ToDecimal(newSal))
            ' now, you need somewhere, something to store emp in               

            Console.WriteLine(line)
        End While
    End Using    

Alternatively, if the text lines were "Ziggy Dunbar, 1500.00", you could read one line per loop interation, split it at "," to get the data. As is, if the file has a name with no salary, it will get out of synch and crash.