How do I indicate that a combo box has been populated with a selection?-CodePudding

I am attempting to create a form in Powershell. It contains a ComboBox dropdown option that I am using as a required field. Until an option is selected, the continue button will be disabled. This is the code for the ComboBox and the button enabling:

$TSTypeBox.Name = "TSType"
$TSTypeBox.Location = New-Object System.Drawing.Point(116,100)
$TSTypeBox.Size = New-Object System.Drawing.Size(145,20)
$TSTypeBox.add_MouseHover($ShowHelp)
$TSTypeBox.DropDownStyle = "DropDownList"
Foreach ($item in ("1","2","3","4","5")) {
    $TSTypeBox.Items.Add($item) | Out-Null
    }
$TSTypeBox.SelectedItem = $TSLocation
$handler_TSTypeBox_SelectedIndexChanged= {
        If (($TSTypeBox.Text) -and ($ComputerNameBox.Text)) 
        {
            $OKButton.Enabled = 1
        }
        Else 
        {
            $OKButton.Enabled = 0
        }
    }
$TSTypeBox.add_SelectedIndexChanged($handler_TSTypeBox_SelectedIndexChanged)

This code in particular works as intended so I'm not worried about that. I am here about the $TSTypeBox.SelectedItem = $TSLocation line that I included. I have code elsewhere that pulls the IP address of the computer the program is being run on, which is then matched against an if/elseif/else statement to determine if the computer belongs to 1 or to 2, which are options that you can see were added to the ComboBox in the code above.

That if/else statement updated the $TSLocation variable which I then use to force the selection of one of the dropdown options in the ComboBox. This works as well, but unfortunately it does not enable the continue button as I would like. I had a hard time looking up issues about this because its super particular and I am probably doing this incorrectly (I have very little experience with Powershell scripting). If you have any additional questions about this please let me know. Thanks!

CodePudding user response：

Ok, this might illustrate your problem.

Just because you set the SelectedItem value to something, doesn't mean the SelectedIndex changes

#
Add-Type -AssemblyName System.Windows.Forms -ErrorAction Stop
#
$TSLocation = '2'
#
$form = New-Object System.Windows.Forms.Form
$form.Text = "Test"
$form.MinimumSize = '430,495'
$form.MaximumSize = '430,545'
$form.StartPosition = 'CenterScreen'
#
# Add form objects
#
$TSTypeBox = New-Object System.Windows.Forms.ComboBox
$TSTypeBox.Name = "TSType"
$TSTypeBox.Location = '116,100'
$TSTypeBox.Size = '145,20'
$TSTypeBox.add_MouseHover($ShowHelp)
$TSTypeBox.DropDownStyle = "DropDownList"
Foreach ($item in ("1","2","3","4","5")) {
    $TSTypeBox.Items.Add($item) | Out-Null
    }

$ComputerNameBox = New-Object System.Windows.Forms.TextBox
$ComputerNameBox.Location = '120,20'
$ComputerNameBox.Size = '120,17'
$ComputerNameBox.Text = 'test'

$OutputBox = New-Object System.Windows.Forms.TextBox
$OutputBox.Location = '120,240'
$OutputBox.Size = '120,17'

$OkButton = New-Object System.Windows.Forms.Button
$OkButton.Location = '120,200'
$OkButton.Size = '54,24'
$OkButton.Text = 'OK'

$form.controls.AddRange(@($TSTypeBox,$OkButton,$ComputerNameBox,$OutputBox))
#
# Main Script goes here
#
$handler_TSTypeBox_SelectedIndexChanged= {
    $OutputBox.Text = "SelectedIndex is "   $TSTypeBox.SelectedIndex
        If (($TSTypeBox.Text) -and ($ComputerNameBox.Text)) 
        {
            $OKButton.Enabled = 1
        }
        Else 
        {
            $OKButton.Enabled = 0
        }
    }
$TSTypeBox.add_SelectedIndexChanged($handler_TSTypeBox_SelectedIndexChanged)

#
$TSTypeBox.SelectedIndex = $TSTypeBox.FindStringExact($TSLocation)
#
# Show form
$form.ShowDialog() | Out-Null
$form.Dispose()
# End

If in doubt, always best to simplify your script and add debug ,logging or output that shows what values are changing

Now that the problem is clear - this article points you in the right direction:

How do I set the selected item in a comboBox to match my string using C#?