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DataGridView column configuration VB.NET

Introduction

This article provides the ability to allow columns in a DataGridView to be rearranged plus showing/hiding columns from a modal form which saves their selection to a XML file stored in the application folder. By providing this functionality users of your application may place columns in the order they suits them as each user working within the application. For instance, one user wants contact phone numbers to the right of the contact name while another user does not want to see several columns as they are not important to task they are performing which are different then the first user.

Also shown is freezing columns similarly to freezing columns in Microsoft Excel.

Users may not consider these features until after using the application for sometime after using the application which means the features are left out completely or will be in an update to the application in the future.

Since each configuration file is the name of the DataGridView this means you can store each DataGridView in a separate file rather then be concerned with a relational XML structure. If the decision is made to use one XML file for several DataGridView controls in an application then change the current name from the single DataGridView name to a name of your choice since each record has the DataGridView name and when read into a DataSet a DataGridView is represented by a DataTable. So adding more DataGridView controls with unique names provide the ability to have all of them in one XML file

Since this code is not tied to My.Settings and app.config but instead a stand along XML file one option is to store the XML file in the user’s My Document folder using code as shown in the following Microsoft code sample instead of in the application folder which is how this code sample has been setup.

XML configuration file structure

In the following XML sample file there is one DataGridView named DataGridView1 with several columns, column name, visible, display index.

<?xml version="1.0" standalone="yes"?>
<DataGridViewConfigurations>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>City</ColumnName>
    <DisplayIndex>0</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>Country</ColumnName>
    <DisplayIndex>1</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>ContactName</ColumnName>
    <DisplayIndex>2</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>ContactTitle</ColumnName>
    <DisplayIndex>3</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>CompanyName</ColumnName>
    <DisplayIndex>4</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>Phone</ColumnName>
    <DisplayIndex>5</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>false</Visible>
    <ColumnName>CustomerIdentifier</ColumnName>
    <DisplayIndex>6</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>Address</ColumnName>
    <DisplayIndex>7</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>PostalCode</ColumnName>
    <DisplayIndex>8</DisplayIndex>
  </DataGridView1>
  <DataGridView1>
    <Visible>true</Visible>
    <ColumnName>Fax</ColumnName>
    <DisplayIndex>9</DisplayIndex>
  </DataGridView1>
</DataGridViewConfigurations>

Configuration class

When creating an instance of this class the intended DataGridView and XML file name is passed into the constructor and set to public properties.
The method InitialRead will read in the file (which was passed into the constructor) if it exists and setup the DataGridView columns. ConfigurationRead method is responsible for setting up a modal form which shows current column display index and Visible property in a DataGridViewCheckBox. Checking the DataGridViewCheckBox will toggle the Visible property of that column. There are two buttons which provide the ability to move the current column left of right.

The Save method accepts the current DataGridView which writes changes back to the XML file.

Imports System.Windows.Forms
 
Public Class  DataGridViewConfiguration
    Inherits BaseExceptionsHandler
 
    Public Property  XmlFileName As  String
    Public Property  DataGridView() As  DataGridView
    Public Table As New  DataTable
    Public FilledFromXml As Boolean
    Private _dataSetRootName As String  = "DataGridViewConfigurations"
    Private _ds As New  DataSet With  {.DataSetName = _dataSetRootName}
    Public Sub  New()
 
    End Sub
    Public Sub  New(pDataGridView As DataGridView, pFileName As String)
        DataGridView = pDataGridView
        XmlFileName = pFileName
        FilledFromXml = False
    End Sub
    ''' <summary>
    ''' Read columns from the xml file when initially loading a DataGridView
    ''' </summary>
    Public Sub  InitialRead()
 
        Try
            If IO.File.Exists(XmlFileName) Then
 
                For Each  col In  DataGridView.Columns.Cast(Of DataGridViewColumn)().ToList
                    col.Visible = False
                Next
 
                Dim ds As New  DataSet
                ds.ReadXml(XmlFileName)
 
                Dim temp = ds.Tables(DataGridView.Name)
 
                For rowIndex As Integer  = 0 To  temp.Rows.Count - 1
                    DataGridView.Columns(CStr(temp.Rows(rowIndex).Item("ColumnName"))).Visible =
                        CBool(temp.Rows(rowIndex).Item("Visible"))
                    DataGridView.Columns(CStr(temp.Rows(rowIndex).Item("ColumnName"))).DisplayIndex =
                        CInt(temp.Rows(rowIndex).Item("DisplayIndex"))
                Next
 
            End If
        Catch ex As Exception
            mHasException = True
            mLastException = ex
        End Try
 
    End Sub
    ''' <summary>
    ''' Read in xml file to populate the DataGridView in DisplayColumns form
    ''' </summary>
    ''' <returns></returns>
    Public Function  ConfigurationRead() As Boolean
 
        mHasException = False
 
        Try
            Table.TableName = DataGridView.Name
            Table.Columns.AddRange(New DataColumn() _
                {
                    New DataColumn("Visible", GetType(Boolean)),
                    New DataColumn("ColumnName", GetType(String)),
                    New DataColumn() With {.ColumnName = "DisplayIndex", .DataType = GetType(Integer)}
                })
 
            If IO.File.Exists(XmlFileName) Then
 
                FilledFromXml = True
                _ds.ReadXml(XmlFileName)
 
                Dim tempTable = _ds.Tables(DataGridView.Name)
 
                For rowIndex As Integer  = 0 To  tempTable.Rows.Count - 1
                    '
                    ' Since a xsd file is not used each value must be type cast
                    '
                    Table.Rows.Add(
                    CBool(tempTable.Rows(rowIndex).Item(0)),
                    tempTable.Rows(rowIndex).Item(1),
                    CInt(tempTable.Rows(rowIndex).Item(2)))
                Next
            Else
                If Not  FilledFromXml Then
                    For Each  col As  DataGridViewColumn In DataGridView.Columns
                        Table.Rows.Add(New Object() {col.Visible, col.Name})
                    Next
                End If
            End If
        Catch ex As Exception
            mHasException = True
            mLastException = ex
        End Try
 
        Return IsSuccessFul
 
    End Function
    ''' <summary>
    ''' Responsible for saving changes made in DisplayColumns form
    ''' Apply button
    ''' </summary>
    ''' <param name="gridView"></param>
    ''' <returns></returns>
    Public Function  Save(ByRef  gridView As  DataGridView) As  Boolean
        mHasException = False
 
        Try
            For rowIndex As Integer  = 0 To  Table.Rows.Count - 1
 
                Dim row = Table.Rows(rowIndex)
 
                row.SetField(Of Integer)("DisplayIndex", rowIndex)
 
                gridView.Columns(row.Field(Of String)("ColumnName")).Visible =
                    row.Field(Of Boolean)("Visible")
 
                If gridView.Columns(row.Field(Of String)("ColumnName")).Visible Then
                    gridView.Columns(row.Field(Of String)("ColumnName")).DisplayIndex =
                        row.Field(Of Integer)("DisplayIndex")
                End If
 
            Next
 
            Dim ds As New  DataSet With  {.DataSetName = _dataSetRootName}
            ds.Tables.Add(Table.Copy())
            ds.WriteXml(XmlFileName)
 
        Catch ex As Exception
            mHasException = True
            mLastException = ex
        End Try
 
        Return IsSuccessFul
 
    End Function
 
End Class

Usage

In the form which will be configured, create an instance of the class DataGridViewConfiguration passing in the DataGridView instance and the file name for the XML file. Since the instance of this class is needed twice it';s setup as a private variable to the form. The XML file name is also setup as a private variable as it's used also in the setup to display the modal form to allow configuration of the columns for the current DataGridView.

Public Class  Form1
    Private _dOperations As DataGridViewConfiguration
    Private _fileName As String  = ""

Then in form load (or form shown) event the InitalRead method is called to setup the column display index and visibility for each column in the DatagridView.

Private Sub  Form1_Load(sender As  Object, e As EventArgs) Handles MyBase.Load
 
    _fileName = IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, DataGridView1.Name & ".xml")
 
    Dim ops As New  DataOperations
    _bsCustomers.DataSource = ops.CustomerView
    DataGridView1.DataSource = _bsCustomers
 
    _dOperations = New  DataGridViewConfiguration(DataGridView1, _fileName)
    _dOperations.InitialRead()
 
    If Not  _dOperations.IsSuccessFul Then
        MessageBox.Show(_dOperations.LastExceptionMessage)
    End If
 
End Sub

To display the modal configuration form from a button click event.

Private Sub  cmdShowHide_Click(sender As Object, e As  EventArgs) Handles  cmdShowHide.Click
 
    Dim f As New  frmDisplayColumns(DataGridView1, _fileName)
    Try
        f.ShowDialog()
    Finally
        f.Dispose()
    End Try
 
End Sub

Next is the configuration form code which you as a developer do not have to touch. What is important to understand is the move columns left/right have been written into language extensions which can only be used when targeting 3.5 framework or higher.

Imports System.Text
Imports TeamLibrary
 
Public Class  frmDisplayColumns
 
    Private _bsColumns As New  BindingSource
    Private _gridView As DataGridView
    Private _dOperations As New  DataGridViewConfiguration
 
    ''' <summary>
    ''' Read in column properties if configuration file exists.
    ''' </summary>
    ''' <param name="dgv">DataGridView to configure</param>
    Public Sub  New(ByRef dgv As DataGridView, pFileName As String)
 
        InitializeComponent()
 
        _gridView = dgv
 
        Text = String.Concat("Columns for ", _gridView.Parent.Name, ".", _gridView.Name)
        _dOperations = New  DataGridViewConfiguration(dgv, pFileName)
 
        _dOperations.ConfigurationRead()
 
    End Sub
    ''' <summary>
    ''' Setup DataGridView with current settings
    ''' </summary>
    ''' <param name="sender"></param>
    ''' <param name="e"></param>
    Private Sub  DisplayColumns_Shown(ByVal sender As Object, ByVal  e As  EventArgs) Handles  Me.Shown
        _bsColumns.DataSource = _dOperations.Table
 
        DataGridView1.DataSource = _bsColumns
 
        DataGridView1.Columns("Visible").HeaderText = "Visible"
        DataGridView1.Columns("ColumnName").HeaderText = "Column name"
        DataGridView1.Columns("ColumnName").AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill
        DataGridView1.Columns("ColumnName").ReadOnly = True
        DataGridView1.Columns("DisplayIndex").Visible = False
 
    End Sub
    ''' <summary>
    ''' Apply settings to DataGridView which was passed in
    ''' </summary>
    ''' <param name="sender"></param>
    ''' <param name="e"></param>
    Private Sub  cmdApply_Click(ByVal  sender As  System.Object, ByVal  e As  EventArgs) Handles  cmdApply.Click
        _dOperations.Save(_gridView)
    End Sub
    ''' <summary>
    ''' Set all columns visible = true
    ''' </summary>
    ''' <param name="sender"></param>
    ''' <param name="e"></param>
    Private Sub  cmdSetAllVisible_Click(sender As Object, e As  EventArgs) Handles  cmdSetAllVisible.Click
        Dim dt As DataTable = CType(_bsColumns.DataSource, DataTable)
        For rowIndex As Integer  = 0 To  dt.Rows.Count - 1
            dt.Rows(rowIndex).SetField(Of Boolean)("Visible", True)
        Next
    End Sub
    Private Sub  cmdUp_Click(sender As Object, e As  EventArgs) Handles  cmdUp.Click
        DataGridView1.MoveRowUp(_bsColumns)
    End Sub
    Private Sub  cmdDown_Click(sender As Object, e As  EventArgs) Handles  cmdDown.Click
        DataGridView1.MoveRowDown(_bsColumns)
    End Sub
    Private Sub  cmdClose_Click(ByVal  sender As  System.Object, ByVal  e As  EventArgs) Handles  cmdClose.Click
        Close()
    End Sub
End Class

All functionality to rig up the above functionality is to add the included team project into your solution and reference the classes in your form(s).

The last thing to discuss is freezing columns. This is done by simply selecting a column in the DataGridView and setting it's Frozen property to True or False as shown in code which is included in the source code for this article.

Private Sub  FrozenToolStripMenuItem_Click(sender As Object, e As  EventArgs) Handles  FrozenToolStripMenuItem.Click
 
    If FrozenToolStripMenuItem.Text = "Freeze" Then
 
        For i As Integer  = 0 To  DataGridView1.Columns.Count - 1
            DataGridView1.Columns(i).Frozen = False
        Next
 
        DataGridView1.Columns(DataGridView1.CurrentCell.ColumnIndex).Frozen = True
 
    Else
        DataGridView1.Columns(DataGridView1.CurrentCell.ColumnIndex).Frozen = False
    End If
 
End Sub

There is an issue which needs to be addressed when dealing with reordering columns when there is one or more frozen columns, reordering is not permitted. To get around this a check is needed to determine if there are any frozen columns.


To handle this a private variable is added to the DisplayColumns form, _hasFrozenColumns. In the form constructor a check is done to determine if there is at least one frozen column. Note My.Dialogs.Question is a custom My.Namespace included in the source code.

_hasFrozenColumns = _gridView.Columns.Cast(Of DataGridViewColumn).
    Any(Function(col) col.Frozen)

Then in form Shown event (the code is placed here as it's best practice to show a message while the current form is showing rather than before it displays so not to confuse the user)

If _hasFrozenColumns Then
 
    If My.Dialogs.Question("Can not reorder columns with frozen columns, would you like unfreeze the columns?") Then
        For colIndex As Integer  = 0 To  _dOperations.DataGridView.Columns.Count - 1
            _dOperations.DataGridView.Columns(colIndex).Frozen = False
        Next
    Else
        cmdApply.Enabled = False
        cmdSetAllVisible.Enabled = False
    End If
 
End If

If the user pressed enter, the Apply and All Visible buttons are disabled as the Question method defaults to No rather than Yes as with MessageBox. The behavior can be changed or an overloaded method for Question can be added which permits the developer to select the Yes button rather than the No button.

Requirements for running the code for this article.

  • Data is read into the DataGridview from a SQL-Server database. This mean you need to have a least SQL-Server Express installed. In the main project locate script.sql to create the database and populate the table which is used to populate our DataGridView.
  • Change the default catalog in DataOperations from KARENS-PC to your SQL Server name or .\SQLEXPRESS.
  • If you are targeting a framework less then 4.6.1 change your project's framework version or change the framework version for team library class project.

Source code repository

https://github.com/karenpayneoregon/DataGridViewConfiguration

See also

DataGridView control
Freeze Columns in the Windows Forms DataGridView Control

Summary

This article and code sample provides easy method to provide the ability for users to maintain column order and visibility of their view into specific data displayed in DataGridView controls in any of your solutions.