下面定义的Show-MessageBox
函数提供了在Windows和macOS上的消息框功能,其模仿了WinForms的MessageBox
类。
示例:
# Message box with custom message, OK button only, and default title and icon
$null = Show-MessageBox 'some message'
# Message box with custom message and title, buttons OK and cancel, and
# the Stop icon (critical error)
# Return value is the name of the button chosen.
$buttonChosen = Show-MessageBox 'some message' 'a title' -Buttons OKCancel -Icon Stop
语法(为了易读性跨多行):
Show-MessageBox [-Message] <string> [[-Title] <string>]
[[-Buttons] {OK | OKCancel | AbortRetryIgnore | YesNoCancel | YesNo | RetryCancel}]
[-Icon {Information | Warning | Stop}]
[-DefaultButtonIndex {0 | 1 | 2}]
注意:
在macOS上,使用AppleScript的display alert命令创建消息框。
尽管此命令分别区分了信息、警告和关键性,但前两个显示相同的图标——一个文件夹,而后者则仅用感叹号覆盖文件夹图标。
为了跨平台一致性,输出值是一个字符串,即用户按下的按钮名称。
- DefaultButtonIndex是按钮的0基索引,当用户只按Enter时将按下该按钮。
- Windows:如果存在“取消”按钮,则按Esc键。
- macOs:如果存在“否”、“中止”或“取消”按钮,并且它不是默认按钮,则按Esc键。
Show-MessageBox源代码:
function Show-MessageBox {
[CmdletBinding(PositionalBinding=$false)]
param(
[Parameter(Mandatory, Position=0)]
[string] $Message,
[Parameter(Position=1)]
[string] $Title,
[Parameter(Position=2)]
[ValidateSet('OK', 'OKCancel', 'AbortRetryIgnore', 'YesNoCancel', 'YesNo', 'RetryCancel')]
[string] $Buttons = 'OK',
[ValidateSet('Information', 'Warning', 'Stop')]
[string] $Icon = 'Information',
[ValidateSet(0, 1, 2)]
[int] $DefaultButtonIndex
)
Set-StrictMode -Off
$buttonMap = @{
'OK' = @{ buttonList = 'OK'; defaultButtonIndex = 0 }
'OKCancel' = @{ buttonList = 'OK', 'Cancel'; defaultButtonIndex = 0; cancelButtonIndex = 1 }
'AbortRetryIgnore' = @{ buttonList = 'Abort', 'Retry', 'Ignore'; defaultButtonIndex = 2; ; cancelButtonIndex = 0 };
'YesNoCancel' = @{ buttonList = 'Yes', 'No', 'Cancel'; defaultButtonIndex = 2; cancelButtonIndex = 2 };
'YesNo' = @{ buttonList = 'Yes', 'No'; defaultButtonIndex = 0; cancelButtonIndex = 1 }
'RetryCancel' = @{ buttonList = 'Retry', 'Cancel'; defaultButtonIndex = 0; cancelButtonIndex = 1 }
}
$numButtons = $buttonMap[$Buttons].buttonList.Count
$defaultIndex = [math]::Min($numButtons - 1, ($buttonMap[$Buttons].defaultButtonIndex, $DefaultButtonIndex)[$PSBoundParameters.ContainsKey('DefaultButtonIndex')])
$cancelIndex = $buttonMap[$Buttons].cancelButtonIndex
if ($IsLinux) {
Throw "Not supported on Linux."
}
elseif ($IsMacOS) {
$iconClause = if ($Icon -ne 'Information') { 'as ' + $Icon -replace 'Stop', 'critical' }
$buttonClause = "buttons { $($buttonMap[$Buttons].buttonList -replace '^', '"' -replace '$', '"' -join ',') }"
$defaultButtonClause = 'default button ' + (1 + $defaultIndex)
if ($null -ne $cancelIndex -and $cancelIndex -ne $defaultIndex) {
$cancelButtonClause = 'cancel button ' + (1 + $cancelIndex)
}
$appleScript = "display alert `"$Title`" message `"$Message`" $iconClause $buttonClause $defaultButtonClause $cancelButtonClause"
Write-Verbose "AppleScript command: $appleScript"
$result = $appleScript | osascript 2>$null
if (-not $result) { $buttonMap[$Buttons].buttonList[$buttonMap[$Buttons].cancelButtonIndex] } else { $result -replace '.+:' }
}
else {
Add-Type -Assembly System.Windows.Forms
[System.Windows.Forms.MessageBox]::Show($Message, $Title, $Buttons, $Icon, $defaultIndex * 256).ToString()
}
}