Save and Read Datagrid View data Into or From a CSV File

Category:

C#, VB.NET, ASP.NET

Type:

Applications

Difficulty:

Beginning

Author:

Anonymous

Version Compatibility: Visual Basic 6, Visual Basic.NET

More information:

This code is useful for those that want an alternative to Microsoft SQL Server or Access. I created this code because I was tired of programming databases with too many strings. There are just two methods. One for writing from the Datagrid control to a file and the other to populate the Datagrid from a file.

Instructions: Copy the declarations and code below and paste directly into your VB project.

Declarations:
' (None)

Code:

Private Sub SaveGridDataInFile(ByRef fName As String)
        'create a new stream(file) writer based on supplied path
        Dim fw As New IO.StreamWriter(fName)
        'write a section for columns collection
        fw.WriteLine("[column]")
        for each column, write the column name within a line
        For x As Short = 0 To DataGridView1.Columns.Count - 1
            
fw.WriteLine(DataGridView1.Columns.Item(x).HeaderText)
        Next
        'write a section for rows collection
        fw.WriteLine("[row]")
        'row controller
        For x As Short = 0 To DataGridView1.Rows.Count - 2
            'for each cell, write the cellvalue followed by a comma
            For y As Short = 0 To DataGridView1.Columns.Count - 1
                fw.Write(DataGridView1.Rows.Item(x).Cells(y).Value + ",")
            Next
            'ends the line
            fw.WriteLine()
        Next
        'close the file writer
        fw.Close()
    End Sub

'this function is to read the file
    Private Sub readfiletodatagrid(ByRef fname As String)
        'create a new stream(file) reader based on supplied path
        Dim fr As New IO.StreamReader(fname)
        'declare few variable to hold position, index, and etc.
        Dim col As Boolean, row As Boolean, colcount As Integer = 0
        Dim currRow As Integer = 0
        While fr.EndOfStream = False
            'get the value of each line
            Dim instring = fr.ReadLine
            If instring = "[column]" Then
                'sets the column controller if in columns section
                col = True
                row = False
                instring = fr.ReadLine
            ElseIf instring = "[row]" Then
                'sets the row controller if in columns section
                row = True
                col = False
                instring = fr.ReadLine
            End If

'adds each column inside a datagridview
            If col = True Then
                DataGridView1.Columns.Add(instring, instring)
                colcount += 1
            End If

'section to get each cell's data
            Dim tempString As String = "", currcell As Integer = 0

If row = True Then
                DataGridView1.Rows.Add()
                For Each c As Char In instring
                    If c = "," Then
                        DataGridView1.Rows(currRow).Cells(currcell).Value = tempString
                        currcell += 1
                        tempString = ""
                    Else
                        tempString += c.ToString
                    End If
                Next
                currRow += 1
            End If
        End While
    End Sub