Convert a GUID into an integer Powershell?

Question

I have a Webservice which tells me this is the function parameters..

    Public Function Create(ByVal Name As String, ByVal templateId As Integer) 

The issue is the templateid is a GUID. if i pass this into the Function the function wont work as it needs to be an integer. I can def say the templateid is a GUID from a SQL database.

so how can i change that GUID into an integer so the function will accept it? is it possible?

all parse tests have come back as false meaning its not possible.

Answer 1

I'm assuming from the function definition that it's Visual Basic, in which the Integer type is a 32 bit signed integer. Even if it were a 64 bit unsigned integer, a [guid] is 128 bits, so its value will not fit into an Integer.

Answer 2

It's not possible to "convert" a GUID into an integer, using conventional means. You could create some special algorithm that performs the conversion, according to your own specification, but there's no standard for this.

There are a couple of options that I see, without having more details about the scenario:

1. Modify the function to accept a GUID as a string
2. Modify the SQL Database to have unique identifiers as integers and GUIDs separately. (not ideal)

Answer 3

Both C# and PowerShell represent GUIDs as 128 bit hyphenated hexadecimal numbers.

It is important to highlight that they are hexadecimal numbers, because the other answers lead you to believe that they are just alphanumeric. The reason for this is that the documentation on C# GUIDs does not explicitly say that they are, however, the constructor and ToString() methods do.

Now, the second problem is that GUIDs are 128 bit. At the time that the other answers were written, .NET's largest integer values were 64 bit. With .NET 7.0, that is no longer true - 128 bit integers are now supported.

So, to answer your question, you can convert a GUID to an Int128 in PowerShell 7.0 by removing the hyphens and parsing it like so:

# C# API:
# static long System.Int128.Parse(string s, System.Globalization.NumberStyles style)
#
# Relevant NumberStyles Value in PowerShell:
# [System.Globalization.NumberStyles]::HexNumber = 515

[Int128]::Parse( ((New-Guid) -replace "-", ""), 515 )