ComboBox.SelectedItem 给出 Null 值

ComboBox.SelectedItem giving Null value

卡在这卡了一整天。我正在使用 PowerShell 表单创建 UI。其中：

问题

问题是您的变量是在一个函数中设置的，因此它们的范围仅限于该函数。真的没有理由把它放在函数中，而是直接放在 .add_click() 中。或者，如果您觉得需要将它保留在函数中，您可以像使用 $global:ButtonClicked 一样设置变量的范围，并将它们设置为 $global:Link 和 $global:LinkType.

编辑： Order 在 PowerShell 中确实有所不同，所以我确实在你的脚本中移动了一些东西以使其正常工作，但我能够获得值来反映当我把它们放在全局范围内时很好。

$global:Button1Clicked = 0;
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing
[System.Windows.Forms.Application]::EnableVisualStyles()
[System.Windows.Forms.FormClosingEventHandler]

######### code Starts ###########

function Button1_Click()
{
    write-host "Link = $global:link"
    write-host "Link Type = $global:linktype"

}

Function Button2_Click()
{

if ($ComboBox1.SelectedIndex -eq 0)
{
$panel2.Visible = $true
$panel1.Visible = $false
}

if ($ComboBox1.SelectedIndex -eq 1)
{
$panel1.Visible = $true
$panel2.Visible = $false

}


}

####### end of code ######

$Form = New-Object system.Windows.Forms.Form
$Form.ClientSize = '1500,800'
$Form.text = "NextUI "
$Form.BackColor = 'White'
$Form.TopMost = $true
$Form.add_closing(
{
if($global:Button2Clicked)
{
$global:Button2Clicked = 0;

$_.cancel = $true;
}
})

################ Module combo box ################

$ComboBox1 = New-Object system.Windows.Forms.ComboBox
$ComboBox1.text = "Select Module"
$ComboBox1.width = 200
$ComboBox1.height = 20
$ComboBox1.location = New-Object System.Drawing.Point(310, 45)
$ComboBox1.Font = 'Microsoft Sans Serif,10'
$combobox1.items.Add("ControlSettings")
$combobox1.items.Add("NextSettings")


######## file and folder permission #############
$ComboBox2 = New-Object system.Windows.Forms.ComboBox
$ComboBox2.text = "select an option"
$ComboBox2.width = 200
$ComboBox2.height = 20
$ComboBox2.location = New-Object System.Drawing.Point(450, 200)
$ComboBox2.Font = 'Microsoft Sans Serif,10'
$ComboBox2.items.AddRange(@("View","Edit") )
#$ComboBox2.items.Add("Edit") 

$ComboBox3 = New-Object system.Windows.Forms.ComboBox
$ComboBox3.text = "select an option"
$ComboBox3.width = 200
$ComboBox3.height = 20
$ComboBox3.location = New-Object System.Drawing.Point(450, 200)
$ComboBox3.Font = 'Microsoft Sans Serif,10'
$ComboBox3.items.Add("View") 
$ComboBox3.items.Add("Edit")

$panel1 = New-Object system.Windows.Forms.Panel
$panel1.AutoSize = $true
$panel1.Width = 1200
$panel1.Height = 200
$panel1.location = New-Object System.Drawing.Point(50,100)
$panel1.Visible = $false
$panel1.Controls.Add($label3)
$panel1.Controls.Add($comboBox2)
$panel1.BorderStyle = 1


$panel2 = New-Object system.Windows.Forms.Panel
$panel2.AutoSize = $true
$panel2.Width = 1200
$panel2.Height =200
$panel2.location = New-Object system.Drawing.Point(50,100)
$panel2.Visible = $false
$panel2.Controls.Add($label4)
$panel2.Controls.Add($ComboBox3)
$panel2.BorderStyle = 1

$Label1 = New-Object system.Windows.Forms.Label
$Label1.text = "Select Module"
$Label1.AutoSize = $true
$Label1.location = New-Object System.Drawing.Point(35,50)
$Label1.Font = 'segoe ui,9.5'

$Label2 = New-Object system.Windows.Forms.Label
$Label2.text = "SharePoint Settings"
$Label2.AutoSize = $true
$Label2.location = New-Object System.Drawing.Point(35,15)
$Label2.Font = 'Segoe UI Semibold,9.5'

$Label3 = New-Object system.Windows.Forms.Label
$Label3.text = "Choose file and folder permission option"
$Label3.AutoSize = $true
$Label3.location = New-Object System.Drawing.Point(100,200)
$Label3.Font = 'segoe ui,9.5'


$Label4 = New-Object system.Windows.Forms.Label
$Label4.AutoSize = $True
$Label4.text = "File Permission"
$Label4.location = New-Object System.Drawing.Point(100,200)
$Label4.Font = 'Segoe UI ,9.5'


$Button1 = New-Object system.Windows.Forms.Button
$Button1.text = "Start"
$Button1.width = 150
$Button1.height = 30
$Button1.BackColor = '#F6CEE3'
$Button1.DialogResult = [System.Windows.Forms.DialogResult]::OK
$Button1.location = New-Object System.Drawing.Point(500, 700)
$Button1.Font = 'segoe ui,10'
$Button1.Add_Click({
$global:link = $comboBox2.SelectedItem.ToString();
$global:linktype = $comboBox3.SelectedItem.ToString();
Button1_Click;
$global:Button1Clicked = 1;
})

############# Button 'Go' #############

$Button2 = New-Object system.Windows.Forms.Button
$Button2.text = "Go"
$Button2.width = 100
$Button2.height = 30
$Button2.BackColor = '#F6CEE3'
$Button2.DialogResult = [System.Windows.Forms.DialogResult]::OK
$Button2.location = New-Object System.Drawing.Point(680, 43)
$Button2.Font = 'segoe ui,10'
$Button2.Add_Click({
Button2_Click;
$global:Button2Clicked = 1;
})

$form.Controls.Add($Panel1)
$form.Controls.Add($Panel2)
$form.Controls.Add($button1)
$form.Controls.Add($comboBox1)
$form.Controls.Add($button2)
$form.Controls.Add($pictureBox1)
$form.Controls.Add($label1)
$form.Controls.Add($label2)

[void]$Form.Add_Shown({ $Form.Activate() })
[void]$Form.ShowDialog()

当我 运行 设置两个组合框值并单击“开始”时，我在 ISE 中收到文本说明我将 Link 和 LinkType 变量设置为什么，以及能够回显 $global:link 和 $global:linktype 以查看正确分配的值。