In the previous tip you have discovered how ConvertFrom-StringData can turn plain text key-value pairs into a hash table. What’s missing is the other way: turn a hasht able into plain text. With that in place, you’d have a really simple framework to save settings and information to files.
Let’s first create a hash table with some data:
$test = @{ Name = 'Tobias' ID = 12 Conf = 'PowerShell Conference EU' } $test
The result looks like this:
Name Value ---- ----- Conf PowerShell Conference EU Name Tobias ID 12
Now here is the function ConvertFrom-Hashtable that takes a hash table and converts it to plain text:
filter ConvertFrom-Hashtable { $_.GetEnumerator() | ForEach-Object { # get hash table key and value $value = $_.Value $name = $_.Name # escape "\" in strings if ($value -is [string]) { $value = $value.Replace('\','\\') } # compose key-value pair as plain text '{0}={1}' -f $Name, $value } }
Let’s see how the hash table converts:
PS> $test | ConvertFrom-Hashtable Conf=PowerShell Conference EU Name=Tobias ID=12 PS>
You can use ConvertFrom-StringData to go the other way:
PS> $test | ConvertFrom-Hashtable | ConvertFrom-StringData Name Value ---- ----- Conf PowerShell Conference EU Name Tobias ID 12 PS>
So essentially, you can now take your hash table, save it as plain text, and reuse it later:
$test = @{ Name = 'Tobias' ID = 12 Conf = 'PowerShell Conference EU' } $path = "$env:temp\settings.txt" # save hash table as file $test | ConvertFrom-Hashtable | Set-Content -Path $path -Encoding UTF8 notepad $path # read hash table from file Get-Content -Path $path -Encoding UTF8 | ConvertFrom-StringData | Out-GridView
Note that this approach works well for simple string and numeric data. It will not work for complex data types since the conversion does not serialize objects.
