PowerShell tips for using the-F method to bring data into the _powershell

Strings enclosed in double quotes can use variables directly, which is a common technique, such as code:

$name = $host. The Name 
"Your host is called $name."

But there are limits to this technique. If you want to display the object's properties instead of the variable itself, for example, this will fail:

Ps> "Your host is called $host. Name. "
Your host is called System.Management.Automation.Internal.Host.InternalHost.Name.

This is because PS only solves the variable itself (such as $host) and does not support its properties.

At the same time you can't control the format of numbers, execute the following code, and the results appear to have a number of digits:

# Get available spaces in bytes for c:drive 
$freeSpace = ([WMI] ' win32_logicaldisk.deviceid= ' C: '). FreeSpace 
 
# Convert to MB 
$freeSpaceMB = $freeSpace/1mb 
 
# output 
"Your c:drive has $freeSpaceMB MB SPAC E available. "

Here is a-F method to solve these problems at the same time. Just place it on the left side of the template text, and its value will be brought in correctly:

# Insert any data into the text template 
' Your host is called {0}. '-f $host. Name 
 
# Calculate free spaces on c:in MB 
$freeSpace = ([WMI] ' win32_logicaldisk.deviceid= ' C: '). FreeSpace 
$freeSpaceMB = $freeSpace/1mb 

# Output with just one digit after the comma 
' Your c:drive has {0:n1 MB space available. ' F $freeSpaceMB

Now, you see, using-F gives you two advantages: the bracketed placeholder indicates the starting position of the entry parameter, and it also accepts formatting. "N1" represents the retention of 1 decimal places. Can change it to meet your needs.

Supports all PS versions