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System.Runtime.InteropServices.Marshal: SystemDefaultCharSize / SystemMaxDBCSCharSize

SystemDefaultCharSize corresponds to the size (in bytes) of a System.Char on the system (2 for Unicode, 1 for ASCII systems).
SystemMaxDBCSCharSize corresponds to the maximum size of the double byte character set (DBCS) for the current OS.

PowerShell example

write-host "SystemDefaultCharSize: $([System.Runtime.InteropServices.Marshal]::SystemDefaultCharSize)"
write-host "SystemMaxDBCSCharSize: $([System.Runtime.InteropServices.Marshal]::SystemMaxDBCSCharSize)"

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