When writing scripts I like to use PowerShell ISE or VSCode a lot. It simplifies a lot of your daily scripting tasks like IntelliSense or Snippets. But sometimes these little helper don’t tell always the truth. Why? Well, I show you an example which is quite common.
On problem there is if you are working with hash tables is that you have a key value pair and you would like to retrieve a value for a specific key. Like in this example I want to retrieve the value for Key2…
$Hash = @{Key1 = "Value1";Key2 = "Value2"}
If you check the the IntelliSense of $Hash, you could use…
$Hash.Key2
…this would output Value2, that’s correct. But what if you have a hash table and you would like to “search” for a specific key?
Well, if we expose the members using Get-Member we see something like this…
There isn’t anything that could help, so we add a little special power to the Get-Member command using –Force, we receive a lot more info…
One very interesting method to our problem seems the “hidden” Get_Item() method, if we try something like…
$Hash.Get_Item("Key2")
…we will receive the corresponding value “Value2”
How does this help? Well you could easily replace the “Key2” string through a variable if needed.
Update 13.04.2018: Or you could use $Hash[$Variable] for using variables. Thank you @rd_bartram!
If you need to change the value of “Key2” you can just use the Set_Item() method like this…
Hash.Set_Item("Key2", "Value3")
Now the new value is “Value3”.
As you can see it is easily possible to discover new members using Get-Member –Force and if you need to discover a value for a specific key in a hash table use the Get_Item() method.
