Working with .NET properties in Power Shell

Question

I'm trying to measure latency using Test-NetConnection. I've gotten this to work well with Test-Connection, but it's not available everywhere.

Here is what I've done with Test-Connection:

PS:>Test-Connection 8.8.8.8 -count 1 | select ResponseTime

ResponseTime
------------
28

Test-NetConnection does return a property containing latency.

PS:>Test-NetConnection 8.8.8.8

ComputerName           : 8.8.8.8
RemoteAddress          : 8.8.8.8
InterfaceAlias         : eth0
SourceAddress          : REMOVED
PingSucceeded          : True
PingReplyDetails (RTT) : 28 ms

But when I try to refer to this property, I don't get the value.

PS:>Test-NetConnection 8.8.8.8 | select PingReplyDetails

PingReplyDetails
----------------
System.Net.NetworkInformation.PingReply

How can I get the actual value out of the command?

Answer 1

Try this... I've broken it down into two steps for a bit more clarity, but you can combine into a single statement on your own if you'd like.

$data = Test-NetConnection 8.8.8.8 | select -ExpandProperty PingReplyDetails
$data.RoundtripTime

Appears to work for me, as you are going for. Since your question includes different attempts, I trust you should be able to customize to fit your exact needs.

In short, use -ExpandProperty to bring out the details in an object.

Answer 2

Well the problem is that PingReplyDetails (RTT) is not a real property as you can see with the following command and its output, where this 'property' is missing.

PS > Test-NetConnection SomeHost | Get-Member


   TypeName: TestNetConnectionResult

Name                     MemberType Definition                                               
----                     ---------- ----------                                               
Equals                   Method     bool Equals(System.Object obj)                           
GetHashCode              Method     int GetHashCode()                                        
GetType                  Method     type GetType()                                           
ToString                 Method     string ToString()                                        
AllNameResolutionResults Property   System.Object AllNameResolutionResults {get;set;}        
BasicNameResolution      Property   System.Object BasicNameResolution {get;set;}             
ComputerName             Property   string ComputerName {get;set;}                           
Detailed                 Property   bool Detailed {get;set;}                                 
DNSOnlyRecords           Property   System.Object DNSOnlyRecords {get;set;}                  
InterfaceAlias           Property   string InterfaceAlias {get;set;}                         
InterfaceDescription     Property   string InterfaceDescription {get;set;}                   
InterfaceIndex           Property   uint32 InterfaceIndex {get;set;}                         
IsAdmin                  Property   bool IsAdmin {get;set;}                                  
LLMNRNetbiosRecords      Property   System.Object LLMNRNetbiosRecords {get;set;}             
MatchingIPsecRules       Property   ciminstance[] MatchingIPsecRules {get;set;}              
NameResolutionSucceeded  Property   bool NameResolutionSucceeded {get;set;}                  
NetAdapter               Property   ciminstance NetAdapter {get;set;}                        
NetRoute                 Property   ciminstance NetRoute {get;set;}                          
NetworkIsolationContext  Property   string NetworkIsolationContext {get;set;}                
PingReplyDetails         Property   System.Net.NetworkInformation.PingReply PingReplyDetai...
PingSucceeded            Property   bool PingSucceeded {get;set;}                            
RemoteAddress            Property   ipaddress RemoteAddress {get;set;}                       
RemotePort               Property   uint32 RemotePort {get;set;}                             
SourceAddress            Property   ciminstance SourceAddress {get;set;}                     
TcpClientSocket          Property   System.Net.Sockets.Socket TcpClientSocket {get;set;}     
TcpTestSucceeded         Property   bool TcpTestSucceeded {get;set;}                         
TraceRoute               Property   string[] TraceRoute {get;set;}    

As it turns out, it is just a kind of formatting sugar which is defined for the result type (TestNetConnectionResult as seen above) of this Cmdlet. The formatting description for this can be retrieved via the following command:

Get-FormatData TestNetConnectionResult | `
Select -ExpandProperty FormatViewDefinition | ? Name -eq DefaultView | `
Select -ExpandProperty Control | `
Select -ExpandProperty Entries | `
Select -ExpandProperty Items | ? Label -eq "PingReplyDetails (RTT)" | `
Select -ExpandProperty DisplayEntry | `
Select -ExpandProperty Value

which returns

$_.PingReplyDetails.RoundTripTime.ToString() + " ms";

With that information in place you can do the same as well e.g. with the following:

Test-NetConnection 8.8.8.8 | Select @{N = "PingReplyDetails (RTT)"; E = {$_.PingReplyDetails.RoundTripTime.ToString() + " ms"}}