c# - Converting another language to powershell or using the language in powershell

Question

I have found this code

// "url" is the full destination path (including filename, i.e. https://mysite.sharepoint.com/Documents/Test.txt) 

// "cookie" is the CookieContainer generated from Wichtor's code 
// "data" is the byte array containing the files contents (used a FileStream to load) 

System.Net.ServicePointManager.Expect100Continue = false; 
HttpWebRequest request = HttpWebRequest.Create(url) as HttpWebRequest; 
request.Method = "PUT"; 
request.Accept = "*/*"; 
request.ContentType = "multipart/form-data; charset=utf-8"; 
request.CookieContainer = cookie; request.AllowAutoRedirect = false; 
request.UserAgent = "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0)"; 
request.Headers.Add("Accept-Language", "en-us"); 
request.Headers.Add("Translate", "F"); request.Headers.Add("Cache-Control", "no-cache"); request.ContentLength = data.Length; 

using (Stream req = request.GetRequestStream()) 
{ req.Write(data, 0, data.Length); } 

HttpWebResponse response = (HttpWebResponse)request.GetResponse(); 
Stream res = response.GetResponseStream(); 
StreamReader rdr = new StreamReader(res); 
string rawResponse = rdr.ReadToEnd(); 
response.Close();
rdr.Close();

Which apparently successfully uploads a large file to a sharepoint site, however my code is in powershell. Is there anyway to use this in powershell in its form now or even convert this to powershell?

Answer 1

C# code is, as a general rule, easily translated to PowerShell because C# uses the exact same underlying type system and runtime environment as PowerShell (.NET).

A few things to watch out for:

Variable assignment

C# is a type-safe language, meaning that the compiler guarantees the type of a variable and its value, as seen in your example:

HttpWebRequest request = HttpWebRequest.Create(url); 
//     ^          ^      \________________________/^      
//     |          |                  |             |
//     |    variable name            |    statement terminator ";"
// type-name                         |
//                    static method call that returns a 
//                     value we can assign to "request"

In PowerShell:

1. Types are implicit, variables are not bound to a single type (thus no need for a type name)
2. Variable references are prefixed with $
3. To access static members (like the Create() method above), we use the following syntax:
   • [Namespace.TypeName]::Member
4. The ; is unnecessary, a linebreak after a statement implies termination

Thus, the above statement becomes:

$request = [System.Net.HttpWebRequest]::Create($url)

---

Booleans

The two C# boolean keywords (true and false) are, in PowerShell, represented by two automatic variables called $true and $false:

[System.Net.ServicePointManager]::Expect100Continue = $false

---

using

PowerShell doesn't have a construct comparable to C#'s using statement. To ensure disposal of an object that implements IDisposable, you'll have to use try/catch/finally:

$req = $request.GetRequestStream()
try{
    $req.Write($data, 0, $data.Length)
} catch {
    throw $_
} finally {
    if($req){
        $req.Dispose()
    }
}

---

Constructors

PowerShell doesn't have a new keyword for object instantiation, but provides the New-Object cmdlet that can wrap C# constructors:

$rdr = New-Object -TypeName System.IO.StreamReader -ArgumentList $res

Rather than:

StreamReader rdr = new StreamReader(res); 

In PowerShell 5.0 and newer, you can now invoke constructors using the new static method as well:

$rdr = [System.IO.StreamReader]::new($res)

---

Type casting

PowerShell supports both explicit casting that in C# would look like (typename)variable, but again, with square brackets instead of parentheses:

[System.Net.HttpWebResponse]$request.GetResponse()

And (as of version 3.0) it supports unchecked casting as well (still with square brackets):

$request.GetResponse() -as [System.Net.HttpWebResponse]

The latter will return $null, rather than throw an error, if the cast is not possible.

---

This should get you translating in no time. From the comments in your codefind, it seems you might need to translate "Wichtor's code" as well, in order to generate the $cookie container.