Script to break up files by namespaces

split-files.ps1

param (
    [string] $FileName
)

$GeneratedFileHeader = "//------------------------------------------------------------------------------
// <auto-generated>
//     This code was generated by a tool.
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// </auto-generated>
//------------------------------------------------------------------------------
"

$lines = [System.IO.File]::ReadAllLines((Join-Path -Path $PSScriptRoot -ChildPath $FileName))

foreach($line in $lines) { 
    switch -regex -casesensitive ($line) {
        '^namespace (.*) \{' {
            if ($OutputFileStream -ne $null) {
                $OutputFileStream.Close()
            }
            $NewFile = $Matches[1] + '.cs'
            $OutputFileStream = New-Object io.streamwriter (Join-Path -Path $PSScriptRoot -ChildPath $NewFile)
            $OutputFileStream.WriteLine($GeneratedFileHeader)
            $OutputFileStream.WriteLine($_)
        }
        default { 
            if ($OutputFileStream -ne $null) {
                $OutputFileStream.WriteLine($_)
            }        
        }
    }
}