How to output data from Structure to CSV using StringBuilder

Question

I have data in the following structure:

Structure student
    Dim stdntpass As String
    Dim fname As String
    Dim sname As String
    Dim age As Byte
    Dim year As Integer
    Dim stdntuser As String
End Structure

I need to take the data in that structure and output it to CSV. I was planning on using a StringBuilder object to do it, but I can't figure out how to give the structure to the StringBuilder.

Answer 1

Here is a function that uses reflection to determine what fields exist in the student structure:

Public Function StudentsToCSV(students As IEnumerable(Of student)) As String
    Const separator As Char = ";"c
    Dim sb As New StringBuilder

    'Get the data elements
    Dim studentFields = GetType(student).GetFields()

    'Output headline (may be removed)
    For Each field In studentFields
        sb.Append(field.Name)
        sb.Append(separator)
    Next
    sb.AppendLine("")

    'Write a line for each student
    For Each s In students
        'Write the value of each field
        For Each field In studentFields
            Dim value As String = Convert.ToString(field.GetValue(s))
            sb.Append(value)
            '... followed by the separator
            sb.Append(separator)
        Next
        sb.AppendLine("")
    Next
    Return sb.ToString()
End Function

You can pass any set of students to this function - may it be an array, a List(Of student) or whatever.