Pass null instead of double quotes in Powershell ConvertTo-Json

Question

I'm passing a value to my JSON body for Invoke-RestMethod via PowerShell

Instead of passing null it passes "" as below:

$usermail = $null | ConvertTo-Json

I'm expecting $usermail to be null but instead its appearing as ""

Please let me know if there is any workaround as my POST method to Graph API fails as a result of bad request due to double quotes. Its expecting value as null instead.

Answer 1

This won't work: $usermail = $null | ConvertTo-Json

The variable "$usermail" is assigned a value of $null. Then $usermail is (supposed to be) passed into the pipe. But a $null value is never passed into a pipe. Because there's nothing in the pipe the "ConvertTo-Json" is never executed.

Does this produce what you were expecting?

[PSCustomObject]@{usermail=$null} | ConvertTo-Json  
{  
    "usermail":  null  
}