How to use GUID in C#

What is GUID?

Globally Unique Identifier is a globally unique value.

When programming, you need a globally unique variable value, and that's when you use GUID.

How to use Guid

Create Guid

Guid guid = Guid.NewGuid();
Console.WriteLine(guid);

Simple.

• Result

Guid empty value check

Guid guid = new Guid();
if(guid == Guid.Empty)
{
Console.WriteLine(guid);
}

When you do new Guid(), 000.. is entered as an empty value. At this time, you can check with Guid.Empty.

• Result

Convert to string ToString

var guid = Guid.NewGuid();
var str = guid.ToString();
Console.WriteLine(guid);

In actual use, when inserting into a DB, there are many cases where it is converted to a string and inserted. In this case, you can easily convert it to a string with ToString.

• Result

Convert string to Guid format Phrase

var str = "fbd05b49-aedd-4417-bec8-5103a221d338";
var guid = Guid.Parse(str);
Console.WriteLine(guid);

This time, when converting a string to Guid format, use Parse.

• Result