检测PowerShell开关

Question

我正在使用C#开发PowerShell cmdlet,并且具有true/false switch语句.我注意到我需要指定-SwitchName $ true,如果我想要bool为true,否则我得到:

Missing an argument for parameter 'SwitchName'. Specify a parameter of type 'System.Boolean' and try again.

开关装饰如下:

        [Parameter(Mandatory = false, Position = 1,
        , ValueFromPipelineByPropertyName = true)]

我怎样才能检测到交换机的存在(-SwitchName设置为true,缺少-SwitchName表示为false)？

Answer 1

要将参数声明为switch参数,您应该将其声明为type System.Management.Automation.SwitchParameter而不是System.Boolean.顺便说一下,有可能区分三种状态的开关参数:

Add-Type -TypeDefinition @'
    using System.Management.Automation;
    [Cmdlet(VerbsDiagnostic.Test, "Switch")]
    public class TestSwitchCmdlet : PSCmdlet {
        private bool switchSet;
        private bool switchValue;
        [Parameter]
        public SwitchParameter SwitchName {
            set {
                switchValue=value;
                switchSet=true;
            }
        }
        protected override void BeginProcessing() {
            WriteObject(switchSet ? "SwitchName set to \""+switchValue+"\"." : "SwitchName not set.");
        }
    }
'@ -PassThru|Select-Object -ExpandProperty Assembly|Import-Module

Test-Switch
Test-Switch -SwitchName
Test-Switch -SwitchName: $false