如何在 Powershell 中将开关参数标记为强制
我很确定除了我发现的之外我没有任何其他选择，但我想选择集体的互联网大脑。
在将布尔值传递给自定义函数时，我更喜欢使用 [switch] 参数。但是，在某些情况下，我想将 switch 参数标记为强制参数。这可以选择通过参数上的[parameter(Mandatory = $true)] 来完成。但是，我真的不喜欢出现的 UI 提示。我更喜欢抛出异常。
但是，开关可以是 true 或 false，并且“IsPresent”属性没有区别。如果我将开关参数作为 -example:$false 传递，则开关会报告 $example.IsPresent 为 false！
我已经求助于使用[bool]。例如：
param
(
[bool]$theValue = $(throw('You didn't specify the value!'))
);
我还有其他的技巧吗？
I'm pretty sure I don't have any other options other than what I've uncovered, but I wanted to pick the collective internet brain.
I prefer to use a [switch] parameter when passing boolean values to custom functions. However, I have a few cases in which I wanted to mark the switch parameter as mandatory. This can optionally be accomplished through [parameter(Mandatory = $true)] on the parameter. However, I really dislike the UI prompt that shows up. I much prefer throwing an exception.
But, a switch can be either true or false, and the "IsPresent" property makes no distinction. If I pass a switch parameter as -example:$false, the switch reports that $example.IsPresent is false!
I have resorted to using a [bool]. For example:
param
(
[bool]$theValue = $(throw('You didn't specify the value!'))
);
Are there any other tricks I can pull?
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在某种程度上，
switch参数始终是必需的。如果您不指定它，它将获得 false 值。如果您指定它 (-var)，它会获取值 true，如果您也指定该值 (-var:$false)，它会获取指定的值。我真的无法想象强制指定开关的情况。如果不指定，则为 false。就这么简单。
我想你想要的是具体提及参数的值是 true 还是 false？如果是这种情况，您提到的
bool版本就是我想要的，尽管它与switch的工作方式也相同：并且还涉及
$ example.IsPresent- 我知道它不直观 /broken ，但它与 switch 变量本身的值相同。这就是Switch Paramater的构造函数的定义方式，它唯一的属性是IsPresent：http:// /msdn.microsoft.com/en-us/library/system.management.automation.switchparameter.ctor%28v=vs.85%29.aspx
In a way a
switchparameter is always mandatory. If you don't specify it, it gets a value of false. If you specify it (-var) it gets a value true and if you specify the value too (-var:$false) it gets the value specified.I can't really think of a situation where it is mandatory to specify a switch. If you don't specify, it is false. Simple as that.
I think what you want is to specifically mention the value of the param to be true or false? If that is the case, the
boolversion that you mention is what I would go for, though it works the same way withswitchtoo:And also regarding
$example.IsPresent- I know it is not intuitive /broken , but it is the same as the value of the switch variable itself. That is how the constructor forSwitch Paramateris defined and the only property that it has is theIsPresent:http://msdn.microsoft.com/en-us/library/system.management.automation.switchparameter.ctor%28v=vs.85%29.aspx