Replace command in powershell is deleting the whole content - powershell

Question

I am new to powershell. I create a powershell script which need to search a string in the path provided in parameters and replace that string. But actually it is replacing entire file content with new string.
I am using Powershell in Windows 10 OS.
Code:
param(
[Parameter(Mandatory=$true, ParameterSetName="Path", Position=0,HelpMessage='Data folder Path')]
[string] $Path,
[Parameter(Mandatory=$true, HelpMessage='Input the string to be replaced')]
[string] $Input,
[Parameter(Mandatory=$true,HelpMessage='Input the new string that need to be replaced')]
[string] $Replace
)
$a = Test-Path $Path
IF ($a -eq $True) {Write-Host "Path Exists"} ELSE {Write-Host "Path Doesnot exits"}
$configFiles = Get-ChildItem -Path $Path -include *.pro, *.rux -recurse
$Append = join-path -path $path \*
$b = test-path $Append -include *.pro, *.rux
If($b -eq $True) {
foreach ($file in $configFiles)
{
(Get-Content $file.PSPath) |
Foreach-Object { $_ -replace [regex]::Escape($Input), $Replace } |
Set-Content $file.PSPath
}
$wshell = New-Object -ComObject Wscript.Shell
$wshell.Popup("Operation Completed",0,"Done",0x0)
}

Answer 1

As best I can read this without directly reproducing it, this is where it goes wrong:
(get-content $file.pspath) gets the entire content of the file, not its name.
Your "foreach" then regexes every line in the file, and finally "set-content" replaces the contents of the file, not its path.
If you want to change the name of a file, you are looking for Rename-Item, not Set-Content. If you want the name of a file $file.Name will do, you don't need Get-Content, which will ... get its content :)

Answer 2

This should be a working solution.
Param(
[Parameter(Mandatory,
ParameterSetName='Path',
Position=0,
HelpMessage='Data folder Path')]
[String]
$Path,
[Parameter(Mandatory,
HelpMessage='Input the string to be replaced')]
[String]
$StringToReplace,
[Parameter(Mandatory,
HelpMessage='Input the new string that need to be replaced')]
[String]
$ReplacementString
)
If (!(Test-Path $Path)) {
Write-Host 'Path does not exist'
Return
}
Get-ChildItem -Path $Path -Include *.pro,*.rux -Recurse |
? { $_.Name -like "*$StringToReplace*" } |
% { Rename-Item $_ $($ReplacementString+$_.Extension) }
(New-Object -ComObject Wscript.Shell).Popup("Operation Completed",0,"Done",0x0)