PowerShell Data Types: Complete Guide with Examples

Question 1

What data types does PowerShell have?

Accepted Answer

PowerShell can use any .NET type. The common ones are [int], [long], [double], [decimal], [string], [char], [bool], [datetime], arrays, [hashtable] and [pscustomobject].

Question 2

How do I check the data type of a variable?

Accepted Answer

Call .GetType().Name on it, for example $total.GetType().Name, or test it with -is, as in $total -is [int].

Question 3

How do I convert a string to a number in PowerShell?

Accepted Answer

Cast it with [int]'42' or [double]'42.5'. Use '42' -as [int] to get $null instead of an error when the text isn't a number.

Question 4

Why does [bool]'false' return True?

Accepted Answer

Casting any non-empty string to [bool] returns True. Use [System.Convert]::ToBoolean('false') or compare the text instead.

Question 5

Should I use double or decimal for money?

Accepted Answer

Use [decimal]. A double can't store values like 0.1 exactly, so sums can be slightly off.

Question 6

What is a type accelerator?

Accepted Answer

A short name for a .NET type, such as [int] for System.Int32 or [hashtable] for System.Collections.Hashtable.

Question 7

Why does [int]2.5 return 2?

Accepted Answer

.NET rounds to the nearest even number when a value is exactly halfway. Use [math]::Round with MidpointRounding.AwayFromZero to always round up.