通過C＃在Hyper-V WMI V2中應用快照

Question

我正在嘗試在C＃中復制以下PowerShell：

# Details from here are not particularly important but needed for full sample
$vms = gwmi -namespace "root\virtualization\v2" Msvm_ComputerSystem
$vm = $vms[3]
$snapshot = ($vm.GetRelated("Msvm_VirtualSystemSettingData") | Where { $_.ElementName -eq "SnapshotName" })[0]
# end unimportant 

$VMSS = Get-WMiObject -class Msvm_VirtualSystemSnapshotService -namespace root\virtualization\v2
$VMSS.ApplySnapshot($snapshot, $null)

此代碼可以正常工作-快照將按預期方式應用。

在C＃中獲取Msvm_VirtualSystemSettingData實例或Msvm_VirtualSystemSnapshostService實例，我沒有問題。 但是，我似乎ApplySnapshot正確調用ApplySnapshot不管我給我什么，都會收到InvalidOperationException 。 我正在使用Visual Studio生成的WMI代碼進行調用：

public uint ApplySnapshot(ref System.Management.ManagementPath Job, System.Management.ManagementPath Snapshot) {
    if ((isEmbedded == false)) {
        System.Management.ManagementBaseObject inParams = null;
        inParams = PrivateLateBoundObject.GetMethodParameters("ApplySnapshot");
        // following line has been through variations as well with no change -
        // commenting it out, setting to null
        inParams["Job"] = ((System.Management.ManagementPath)(Job)).Path;
        inParams["Snapshot"] = ((System.Management.ManagementPath)(Snapshot)).Path;
        System.Management.ManagementBaseObject outParams = PrivateLateBoundObject.InvokeMethod("ApplySnapshot", inParams, null);
        Job = ((System.Management.ManagementPath)(outParams.Properties["Job"].Value));
        return System.Convert.ToUInt32(outParams.Properties["ReturnValue"].Value);
    }
    else {
        return System.Convert.ToUInt32(0);
    }
}

我也不知道傳遞給Job參數什么，因為我們找回了工作-對此有一個ref而不是一個out是很不尋常的out但是我已經嘗試了很多不同的變化（包括設置參數設置為null並且完全沒有設置）。 我也曾嘗試將inParams[Job]設置為null ，但也沒有運氣。

為了使這項工作有效，我應該更改什么？

Answer 1

我相信您的問題是，當它是出站參數時，您正在傳遞作業。 該參數將從調用中返回。 就像是..

ManagementBaseObject inParams = null;

inParams = PrivateLateBoundObject.GetMethodParameters("ApplySnapshot");
inParams["Snapshot"] = ((System.Management.ManagementPath)(Snapshot)).Path;

ManagementBaseObject outParams = PrivateLateBoundObject.InvokeMethod("ApplySnapshot", inParams, null);

// i left this as i assume this is vs generated though this isn't how i would normally
// get my jobs back.
Job = ((ManagementPath)(outParams.Properties["Job"].Value));

return Convert.ToUInt32(outParams.Properties["ReturnValue"].Value);