如何在Powershell中将字符串连接到文件名？

$baseName = "example"
$extension = ".txt"
$fileName = $baseName + $extension
Write-Output $fileName  # 输出: example.txt

$baseName = "example"
$extension = ".txt"
$fileName = "$baseName$extension"
Write-Output $fileName  # 输出: example.txt

$directoryPath = "C:\path\to\directory"
$baseName = "example"
$extension = ".txt"
$fileName = Join-Path -Path $directoryPath -ChildPath "$baseName$extension"
Write-Output $fileName  # 输出: C:\path\to\directory\example.txt

$baseName = "example?file"
$extension = ".txt"
$fileName = [System.IO.Path]::GetInvalidFileNameChars() | ForEach-Object { $baseName = $baseName.Replace($_, "_") }
$fileName += $extension
Write-Output $fileName  # 输出: example_file.txt

$directoryPath = "C:\path\to\directory"
if (-Not (Test-Path $directoryPath)) {
    New-Item -ItemType Directory -Path $directoryPath
}
$baseName = "example"
$extension = ".txt"
$fileName = Join-Path -Path $directoryPath -ChildPath "$baseName$extension"
Write-Output $fileName  # 输出: C:\path\to\directory\example.txt