如何在PowerShell函数中使用ValidateSet属性？
PowerShell函数中的ValidateSet属性用于验证从集合输入的值，这意味着它仅允许集合中的特定值。为了更好地理解下面的示例，我们有一个数组，我们需要检查输入的值是否在数组中，然后我们将使用以下代码。
Function PetAnimalsCheck {
param(
[String]$Animal
)
$Animals = "Cow","Dog","Cat","Horse","Camel","Elephant"
if($Animals -contains $Animal) {
Write-Output "Animal is in the list of Pet Animals"
} else {
Write-Output "Animal is not Pet Animal"
}
}输出结果
PS C:\> PetAnimalsCheck -Animal Dog Animal is in the list of Pet Animals PS C:\> PetAnimalsCheck -Animal Tiger Animal is not Pet Animal
如果将以上命令替换为ValidateSet属性，则代码将只有几行。
Function PetAnimalsCheck {
param(
[ValidateSet("Cow","Dog","Cat","Horse","Camel","Elephant",ErrorMessage="Ani
mal Name is not among list")]
[String]$Animal
)
Write-Output "Animal is Pet Animal"
}输出结果
PS C:\> PetAnimalsCheck -Animal Tiger PetAnimalsCheck: Cannot validate argument on parameter 'Animal'. Animal Name is not among list PS C:\> PetAnimalsCheck -Animal Cat Animal is Pet Animal
如果需要将其设置为区分大小写，请使用IgnoreCase值。
Function PetAnimalsCheck {
param(
[ValidatepathExi]
[ValidateSet("Cow","Dog","Cat","Horse","Camel","Elephant",ErrorMessage="Ani
mal Name is not among list or case sensitive", IgnoreCase=$false)]
[String]$Animal
)
Write-Output "Animal is Pet Animal"
}输出结果
PS C:\> PetAnimalsCheck -Animal cat PetAnimalsCheck: Cannot validate argument on parameter 'Animal'. Animal Name is not among list or case sensitive PS C:\> PetAnimalsCheck -Animal Cat Animal is Pet Animal