I've been working on a few PowerShell projects recently and one requirement I had was to turn an object into a hash table. I thought this was something that was already handled in PowerShell but I couldn't find a cmdlet or an easy .NET technique. So I wrote my own function, ConvertTo-Hashtable.<\/p>\n
The function is designed to accept pipelined input and turns each object into an associative array, i.e., a hash table, and write the hash table to the pipeline.<\/p>\n
Function ConvertTo-HashTable {\r\n\r\n[cmdletbinding()]\r\n\r\nParam(\r\n[Parameter(Position=0,Mandatory=$True,HelpMessage=\"Please specify an object\",\r\nValueFromPipeline=$True)]\r\n[object]$InputObject,\r\n[switch]$NoEmpty\r\n)\r\n\r\nProcess {\r\nWrite-Verbose \"Converting an object of type $($_.GetType().Name)\"\r\n#get propery names\r\n$names=$InputObject | get-member -MemberType properties | select-object -expandproperty name\r\n#define an empty hash table\r\n$hash=@{}\r\n#go through the list of names and add each property and value to the hash table\r\n$names | foreach-object {\r\nWrite-Verbose \"Adding property $_\"\r\n$hash.Add($_,$inputobject.$_)\r\n} #foreach\r\nif ($noEmpty) {\r\nWrite-Verbose \"Parsing out empty values\"\r\n#define a new hash\r\n$defined=@{}\r\n#get items from $hash that have values and add to $defined\r\n$hash.keys | foreach-object {\r\nif ($hash.item($_)) {\r\n$defined.add($_,$hash.item($_))\r\n}\r\n}\r\nWrite-Verbose \"Writing the result to the pipeline\"\r\nWrite-Output $defined\r\n}\r\nelse {\r\nWrite-Verbose \"Writing the result to the pipeline\"\r\nWrite-Output $hash\r\n} #If $noempty\r\n}#close process\r\n}#end function<\/pre>\nAs an object is processed by the function it uses Get-Member to retrieve all of the object's properties.<\/span><\/p>\n$names=$InputObject | get-member -MemberType properties | select-object -expandproperty name<\/pre>\nThe function then walks the object and adds each property name and value to a hash table.<\/span><\/p>\n#go through the list of names and add each property and value to the hash table\r\n$names | foreach-object {\r\nWrite-Verbose \"Adding property $_\"\r\n$hash.Add($_,$inputobject.$_)\r\n} #foreach<\/pre>\nThis hash table object, $hash, eventually is written to the pipeline. This process happens to each piped in object. However, I also added a function parameter, -NoEmpty, to filter out properties with no values. When specified, the function creates a second hash table and then checks each key in $hash. If the corresponding item has a value, the key and value are added to the secondary hash.<\/span><\/p>\nif ($noEmpty) {\r\nWrite-Verbose \"Parsing out empty values\"\r\n#define a new hash\r\n$defined=@{}\r\n#get items from $hash that have values and add to $defined\r\n$hash.keys | foreach-object {\r\nif ($hash.item($_)) {\r\n$defined.add($_,$hash.item($_))\r\n}\r\n}\r\nWrite-Verbose \"Writing the result to the pipeline\"\r\nWrite-Output $defined<\/pre>\nThe secondary hash is then written to the pipeline. I had to take this approach because PowerShell doesn't like it when you try to modify and enumerate a hash table at the same time. Here's how you might use it:<\/p>\n
PS S:\\> $h=get-service spooler | convertto-hashtable\r\nPS S:\\> $h\r\n\r\nName Value\r\n---- -----\r\nServiceName spooler\r\nCanPauseAndContinue False\r\nDisplayName Print Spooler\r\nCanShutdown False\r\nSite\r\nName spooler\r\nMachineName .\r\nServiceType Win32OwnProcess, InteractiveProcess\r\nStatus Running\r\nServiceHandle SafeServiceHandle\r\nContainer\r\nDependentServices {}\r\nRequiredServices {HTTP, RPCSS}\r\nServicesDependedOn {HTTP, RPCSS}\r\nCanStop True<\/pre>\n