Using PowerShell to do a find and replace on all files and subfolders

I looked around for a while and just couldn't find a script that did this for me. So here it is so I don't lose it. It was useful as part of setting up a new VS2010 project that was a complete copy of the one from another project.

$search = "SearchString"
$replace = "ReplaceString"

function RenameFile ($fileInfo)
{
    if ($fileInfo.Name.Contains($search))
    {
        $newFullName = $fileInfo.DirectoryName + "\" + $fileInfo.Name.Replace($search, $replace)
        Move-Item $fileInfo.FullName $newFullName
        
        return 1
    }
    return 0
}

function RenameDirectory ($dirInfo)
{
    if ($dirInfo.Name.Contains($search))
    {
        $newFullName = $dirInfo.Parent.FullName + "\" + $dirInfo.Name.Replace($search, $replace)
        Move-Item $dirInfo.FullName $newFullName
        
        return 1
    }
    return 0
}

$files = Get-ChildItem -Path . * -Recurse -Force

$i = 0
$j = 0

# Rename files
foreach ($file in $files)
{
    if ($file.GetType().ToString() -eq "System.IO.FileInfo")
    {
        if (RenameFile($file) -eq 1)
        {
            $i = $i + 1
        }
    }
}

# Now rename directories
foreach ($file in $files)
{
    if ($file.GetType().ToString() -eq "System.IO.DirectoryInfo")
    {
        if (RenameDirectory($file) -eq 1)
        {
            $j = $j + 1
        }
    }
}

Write-Host Renamed $i files, $j directories.