PowerShell DataGridView ComboBoxColumn Default Value

Question

I'm trying to set the default value for DataGridViewComboBoxColumn to be a variable, but I can't find which property to set.

$Column2 = New-Object System.Windows.Forms.DataGridViewComboBoxColumn
$Column2.width = 60
$Column2.name = "Status"
$Column2.DataSource = $DropDownArray
$DataGrid.Columns.Add($Column2)

I've tried:

$Column2.Value = "C"
$Column2.ValueMember = $DDI
$Column2.DataPropertyName = $DDI
$Column2.DisplayMember = $DDI
$Column2.Text = $DropDown.SelectedItem
If($Column2.Index -ge "0"){$Column2.ValueMember = "C"}

$DDI calls back to an array item. Assistance is appreciated.

Edit

I am not communicating this well enough, I assume. Here is what I have so far (ignore all the commented out stuff, of course):

$null=[reflection.assembly]::LoadWithPartialName("System.Windows.Forms")
$null=[reflection.assembly]::LoadWithPartialName("System.Drawing")

#Initialize DataGrid stuff
$form = new-object System.Windows.Forms.Form
$form.Size = new-object System.Drawing.Size 800,400
$DataGrid = new-object System.Windows.Forms.DataGridView
#$DataGrid = new-object System.windows.forms.DataGrid
$DataGrid.AutoSize = $True
$DataGrid.EditMode = 'EditOnEnter'
#$DataGrid.BeginEdit()
[array]$DropDownArray = "FVR","C","O","P"
#$DropDownArray = @(Import-Csv "$BkpLoc\array.csv")

#This creates the Ok button and sets the event
$OKButton = New-Object System.Windows.Forms.Button
$OKButton.Location = New-Object System.Drawing.Size(750,375)
$OKButton.Size = New-Object System.Drawing.Size(150,125)
$OKButton.Text = "OK"
$OKButton.Add_Click({$form.Close()})
$OKButton.TabIndex = 9


$array= new-object System.Collections.ArrayList
$data=@(Import-CSV $SAMTemp2)
$array.AddRange($data)
$DataGrid.DataSource = $array

#$DataGrid.Columns.Remove($array.Status)
#Figure out how to set the array to read-only
#$array.IsReadOnly

    $Column1 = New-Object System.Windows.Forms.DataGridViewCheckBoxColumn
    $Column1.width = 60
    $Column1.name = "Planned"
    $DataGrid.Columns.Add($Column1) 

    $Column2 = New-Object System.Windows.Forms.DataGridViewComboBoxColumn
    $Column2.width = 60
    $Column2.name = "Status"
    $Column2.DataSource = $DropDownArray
    $DataGrid.Columns.Add($Column2)

    #$Column2.Selected = $DropDownArray[1]
    #$Column2.DisplayMember = "Status"
    #$Column2.DataPropertyName = $DropDownArray[1]
    #$Column2.ValueMember = $DropDownArray.Item(1)

    $array = New-Object System.Collections.ArrayList
    $form.refresh()

#finally show display the Grid
$DataGrid.Dock = [System.Windows.Forms.DockStyle]::Fill
$form.Controls.Add($DataGrid)

$form.controls.add($OKButton)
$form.topmost = $true
$null = $form.showdialog()

My goal here is to have $Column1 available to check if the task was planned that day (up to the user) and $Column2 to default to the status in the export (FVR, C, O or P), allowing the user to change it to another option if the data is incorrect. So ultimately I would like the default to be set based on a statement like:

If($_.Status -eq "Open"){$Column2.ValueMember = <WHATEVER IT TAKES TO GET THE CURRENT VALUE TO "O">
$Column2.DataPropertyName = <WHATEVER IT TAKES TO GET THE CURRENT VALUE TO "O">
$Column2.DisplayMember = <WHATEVER IT TAKES TO GET THE CURRENT VALUE TO "O">

And the same for each value. ($_.Status is one of the columns in the imported CSV.) Right now I just can't get it right. Should there be more to my array than just the 4 values? Everything I try right now for ValueMember comes back saying Field called -WHATEVER- does not exist.

Answer 1

When you add rows to or data bind your DataGridView you will specify the default or selected value for that column then and it'll get translated to your combobox. ValueMember is what you're looking for as it's associated with the data's actual value as opposed to what's displayed in the combobox (DisplayMember). ValueMember and DisplayMember can be the same but they don't have to be.

See below example. This will create a data source of color names and RGB values.

# Datatable for your CSV content
$DataTable1 = New-Object System.Data.DataTable
[void] $DataTable1.Columns.Add("Fruit")
[void] $DataTable1.Columns.Add("RGB")

# Your CSV content
@"
Fruit,RGB
apple,ff0000
apple,00ff00
kiwi,00ff00
"@ | ConvertFrom-Csv | ForEach-Object {
    [void] $DataTable1.Rows.Add($_.Fruit, $_.RGB)
    }

# Acceptable color values datatable - for your combobox
$DataTable2 = New-Object System.Data.DataTable
[void] $DataTable2.Columns.Add("RGB")
[void] $DataTable2.Columns.Add("Color")
# Manually add rows. You can programmatically add the rows as well 
[void] $DataTable2.Rows.Add("ff0000", "red")
[void] $DataTable2.Rows.Add("00ff00", "green")
[void] $DataTable2.Rows.Add("0000ff", "blue")

# Form
$Form = New-Object System.Windows.Forms.Form
$Form.Size = New-Object System.Drawing.Size(500,500)
$Form.StartPosition = "CenterScreen"

# Form event handlers
$Form.Add_Shown({
    $Form.Activate()
    })

# Datagridview
$DGV = New-Object System.Windows.Forms.DataGridView
$DGV.Anchor = [System.Windows.Forms.AnchorStyles]::Right -bor [System.Windows.Forms.AnchorStyles]::Bottom -bor [System.Windows.Forms.AnchorStyles]::Left -bor [System.Windows.Forms.AnchorStyles]::Top
$DGV.Location = New-Object System.Drawing.Size(0,0) 
$DGV.Size = New-Object System.Drawing.Size(480,400)
$DGV.Font = New-Object System.Drawing.Font("Microsoft Sans Serif",10,0,3,1)
$DGV.BackgroundColor = "#ffffffff"
$DGV.BorderStyle = "Fixed3D"
$DGV.AlternatingRowsDefaultCellStyle.BackColor = "#ffe6e6e6"
$DGV.AutoSizeColumnsMode = [System.Windows.Forms.DataGridViewAutoSizeColumnsMode]::Fill
$DGV.AutoSizeRowsMode = [System.Windows.Forms.DataGridViewAutoSizeRowsMode]::AllCells
$DGV.SelectionMode = [System.Windows.Forms.DataGridViewSelectionMode]::FullRowSelect
$DGV.ClipboardCopyMode = "EnableWithoutHeaderText"
$DGV.AllowUserToOrderColumns = $True
$DGV.DataSource = $DataTable1
$DGV.AutoGenerateColumns = $False
$Form.Controls.Add($DGV)

# Datagridview columns
$Column1 = New-Object System.Windows.Forms.DataGridViewTextBoxColumn
$Column1.Name = "Fruit"
$Column1.HeaderText = "Fruit"
$Column1.DataPropertyName = "Fruit"
$Column1.AutoSizeMode = "Fill"

$Column2 = New-Object System.Windows.Forms.DataGridViewComboBoxColumn
$Column2.Name = "Color"
$Column2.HeaderText = "Color"
$Column2.DataSource = $DataTable2
$Column2.ValueMember = "RGB"
$Column2.DisplayMember = "Color"
$Column2.DataPropertyName = "RGB"

$DGV.Columns.AddRange($Column1, $Column2)

# Button to export data
$Button = New-Object System.Windows.Forms.Button
$Button.Anchor = [System.Windows.Forms.AnchorStyles]::Left -bor [System.Windows.Forms.AnchorStyles]::Bottom
$Button.Location = New-Object System.Drawing.Size(10,420) 
$Button.Text = "Export"
$Form.Controls.Add($Button)

# Button event handlers
$Button.Add_Click({
    $DataTable1 | Out-GridView # do what you want
    })

# Show form
[void] $Form.ShowDialog()