[c#] How to convert a GUID to a string in C#?

I'm new to C#.

I know in vb.net, i can do this:

Dim guid as string = System.Guid.NewGuid.ToString

In C#, I'm trying to do

String guid = System.Guid.NewGuid().ToString;

but i get an "Cannot convert method group 'ToString' to non-delegate type 'string'. Did you intend to invoke the method?" error.

This question is related to c# string guid

The answer is


You're missing the () after ToString that marks it as a function call vs. a function reference (the kind you pass to delegates), which incidentally is why c# has no AddressOf operator, it's implied by how you type it.

Try this:

string guid = System.Guid.NewGuid().ToString();

You need

String guid = System.Guid.NewGuid().ToString();

String guid = System.Guid.NewGuid().ToString();

Otherwise it's a delegate.


According to MSDN the method Guid.ToString(string format) returns a string representation of the value of this Guid instance, according to the provided format specifier.

Examples:

  • guidVal.ToString() or guidVal.ToString("D") returns 32 hex digits separated by hyphens: 00000000-0000-0000-0000-000000000000
  • guidVal.ToString("N") returns 32 hex digits:00000000000000000000000000000000
  • guidVal.ToString("B") returns 32 hex digits separated by hyphens, enclosed in braces:{00000000-0000-0000-0000-000000000000}
  • guidVal.ToString("P") returns 32 hex digits separated by hyphens, enclosed in parentheses: (00000000-0000-0000-0000-000000000000)

Here are examples of output from each of the format specifiers:

N: cd26ccf675d64521884f1693c62ed303
D: cd26ccf6-75d6-4521-884f-1693c62ed303
B: {cd26ccf6-75d6-4521-884f-1693c62ed303}
P: (cd26ccf6-75d6-4521-884f-1693c62ed303)
X: {0xcd26ccf6,0x75d6,0x4521,{0x88,0x4f,0x16,0x93,0xc6,0x2e,0xd3,0x03}}

The default is D.

Run this yourself.


Guid guidId = Guid.Parse("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx");
string guidValue = guidId.ToString("D"); //return with hyphens

you are missing () on the end of ToString.


In Visual Basic, you can call a parameterless method without the braces (()). In C#, they're mandatory. So you should write:

String guid = System.Guid.NewGuid().ToString();

Without the braces, you're assigning the method itself (instead of its result) to the variable guid, and obviously the method cannot be converted to a String, hence the error.


Did you write

String guid = System.Guid.NewGuid().ToString;

or

String guid = System.Guid.NewGuid().ToString();

notice the paranthesis


Following Sonar rules, you should whenever you can try to protect yourself, and use System.globalisation whenever it's possible like for DateTime.ToString().

So regarding the other answers you could use:

guid.ToString("", CultureInfo.InvariantCulture)

where "" can be replaces by : N, D, B , P and X for more infos see this comment.

Example here