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PowerShell: Create a char array from a string

In PowerShell, a string can be converted to a character array with the following simple construct: 
PS C:\> [char[]] 'abcde'
a
b
c
d
e
Alternatively, the string's ToChararray() can be used: 
PS C:\> 'abcde'.ToCharArray()
Lastly, the -split operator can be used together with a positive look-behind and look-ahead regular expression assertion.
However, it should be noted that this operation splits the string into an array of strings, not of characters. 
PS C:\> 'abcde' -split '(?<=.)(?=.)'

See also

System.String.ToCharArray

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