How to call an executable with parameters from powershell script - powershell

Question

I am seeking help on how to call cmd with specific parameters from a powershell script. So far what I have written is below, but it gives me an error message saying $_cmd is not recognized.
I am trying to pass the from date and to date to a an exe... The from date as you can see needs to be today - 1 and the to date should be now. The path of the executable is D:\DataService and that's why I am setting the path early in the script.
Write-Host "Get data from service"
$path ="D:\DataService"
Push-Location $path
$Date = Get-Date
$DateFrom = $Date.ToString("yyyy-MM-dd HH:mm:ss")
$DateTo = $Date.AddDays(-1).ToString("yyyy-MM-dd")
$_cmd = "ReportGen.exe -ReportType Data -DateFrom $DateFrom $DateTo"
%$_cmd%
Any suggestions please?

Answer 1

Don't make a command string. Simply use the call operator (&):
Write-Host 'Get data from service'
$path = 'D:\DataService'
Push-Location $path
$Date = Get-Date
$DateFrom = $Date.ToString('yyyy-MM-dd HH:mm:ss')
$DateTo = $Date.AddDays(-1).ToString('yyyy-MM-dd')
& ReportGen.exe -ReportType Data -DateFrom $DateFrom $DateTo

Answer 2

%$_cmd% looks like a mixture of PowerShell and cmd syntax. The %'s have no special significance. PowerShell interprets that as the literal name of a command, which of course is not recognized. To execute the contents of the string, use
Invoke-Expression $_cmd
However, that will only work if ReportGen.exe is in the path, and cmd doesn't even get involved, because you're not calling it anywhere. If for some reason, as you say, you specifically want to execute that command with cmd, you should add cmd /c or cmd /k at the beginning. However, you don't even need to assign to a string, you can just call cmd directly:
cmd /c ReportGen.exe -ReportType Data -DateFrom $DateFrom $DateTo
/c means that cmd will exit after executing the command. /k means the cmd prompt will remain open after the command is executed. You probably want /c so that you'll return to the PowerShell prompt after executing the script.

Answer 3

You want to use Invoke-Expression as per the comments below.
Invoke-Expression $_cmd
Original comment, which is wrong:
Did you try putting an ampersand in front. e.g.:
& $_cmd
Not sure why you are using the % characters.

Answer 4

A couple things. One, stop using Write-Host. Honestly, let this be the final time you ever use it (unless you truly need it - and know why you need it). Instead, use Write-Output - even when you know your script is going to run in the console. Second, you could also consider using the Start-Process cmdlet and its parameter -ArgumentList.

Answer 5

Your $DateFrom and $DateTo seem to be backwards, since you are making $DateTo set to yesterday. So unless you are going from today to yesterday you may want to adjust that. Also, you specify the from date, but just tack the to date on the end, not sure if you need to specify what it is, or if both dates are a part of the same parameter. As for running a command with arguments, use Invoke-Command with arguments comma delimited as such:
Invoke-Command -FilePath "D:\DataService\ReportGen.exe" -ArgumentList '-ReportType Data','-DateFrom $DateFrom','$DateTo'

Answer 6

I'd do it something like this.
$CustomProcess = New-Object System.Diagnostics.ProcessStartInfo
$CustomProcess.FileName = "ReportGen.exe"
$CustomProcess.arguments = "-ReportType Data -DateFrom $DateFrom $DateTo"
[System.Diagnostics.Process]::Start($CustomProcess)