使用Powershell从VB.NET代码调用PhantomJS脚本

Question

I am currently trying to use phantomJS in order to take a screenshot of a webpage for work. I have the script working correctly and can run it from powershell.

Dim PhantomString As String = $"'{System.Environment.CurrentDirectory}\phantomjs' PhantomJSScript.js {parameter1} {parameter2} {parameter3} {parameter4}"

This is the string that represents the call I use in powershell to execute my PhantomJSScript which is called PhantomJSScript.js. When I try to run this command from my vb.net code, I get the error that the parameters are not recognized tokens. I am using System.Management.Automation.Runspaces.Runspace and other affiliated libraries to execute this.

Using MyRunSpace As Runspace = RunspaceFactory.CreateRunspace
    MyRunSpace.Open()
    Dim MyPipeline As Pipeline = MyRunSpace.CreatePipeline()
    MyPipeline.Commands.AddScript(PhantomString, True)

    Dim pipeLineResult As Collection(Of PSObject) = MyPipeline.Invoke()
    If MyPipeline.Error.Count > 0 Then
        ImageList = Nothing
    Else
        ImageList = (From pipeOut In pipeLineResult Select (pipeOut.ToString)).ToList
    End If
End Using
Return ImageList

This is the code that I am using to run the command. To compensate for the error that pops up where {parameter1} is not a recognized token, I tried to use the parameters property on the command. I added each of the parameters in PhantomString to the command property instead and removed them from PhantomString. This allowed the script to run (or so it seemed) however, it just returned the exact value of PhantomString that I passed in. I was expecting bit representation of the image I requested.

Here is what my code looks like when I try to pass parameters the other way:

    Dim PhantomString As String = $"'{System.Environment.CurrentDirectory}\phantomjs'"

    Using MyRunSpace As Runspace = RunspaceFactory.CreateRunspace
        MyRunSpace.Open()
        Dim MyPipeline As Pipeline = MyRunSpace.CreatePipeline()
        MyPipeline.Commands.AddScript(PhantomString, True)
        MyPipeline.Commands.FirstOrDefault.Parameters().Add("arg1", "PhantomJSScript.js")
        MyPipeline.Commands.FirstOrDefault.Parameters().Add("arg2", $"{parameter1}")
        MyPipeline.Commands.FirstOrDefault.Parameters().Add("arg3", $"{parameter2}")
        MyPipeline.Commands.FirstOrDefault.Parameters().Add("arg4", $"{parameter3}")
        MyPipeline.Commands.FirstOrDefault.Parameters().Add("arg5", $"{parameter4}")

        Dim pipeLineResult As Collection(Of PSObject) = MyPipeline.Invoke()
        If MyPipeline.Error.Count > 0 Then
            ImageList = Nothing
        Else
            ImageList = (From pipeOut In pipeLineResult Select (pipeOut.ToString)).ToList
        End If
    End Using

    Return ImageList

Could anyone please give me some insights on how to get this working properly?

Thanks!

Answer 1

So I have since resolved the problem. Basically, it had to do with the fact that there was a space in the localhost path to the .exe. The way I handled it was by simply moving phantomjs.exe to a different path without spaces in directory names. When this gets moved to dev/staging/live, we don't have to worry about the space because the file path is completely different.