How to try convert a string to a Guid [duplicate]

Question

new Guid(string)

You could also look at using a TypeConverter.

use code like this:

new Guid("9D2B0228-4D0D-4C23-8B49-01A698857709")

instead of "9D2B0228-4D0D-4C23-8B49-01A698857709" you can set your string value

Guid.TryParse()

https://msdn.microsoft.com/de-de/library/system.guid.tryparse(v=vs.110).aspx

or

Guid.TryParseExact()

https://msdn.microsoft.com/de-de/library/system.guid.tryparseexact(v=vs.110).aspx

in .NET 4.0 (or 3.5?)

This will get you pretty close, and I use it in production and have never had a collision. However, if you look at the constructor for a guid in reflector, you will see all of the checks it makes.

 public static bool GuidTryParse(string s, out Guid result)
    {
        if (!String.IsNullOrEmpty(s) && guidRegEx.IsMatch(s))
        {
            result = new Guid(s);
            return true;
        }

        result = default(Guid);
        return false;
    }

    static Regex guidRegEx = new Regex("^[A-Fa-f0-9]{32}$|" +
                          "^({|\\()?[A-Fa-f0-9]{8}-([A-Fa-f0-9]{4}-){3}[A-Fa-f0-9]{12}(}|\\))?$|" +
                          "^({)?[0xA-Fa-f0-9]{3,10}(, {0,1}[0xA-Fa-f0-9]{3,6}){2}, {0,1}({)([0xA-Fa-f0-9]{3,4}, {0,1}){7}[0xA-Fa-f0-9]{3,4}(}})$", RegexOptions.Compiled);

Unfortunately, there isn't a TryParse() equivalent. If you create a new instance of a System.Guid and pass the string value in, you can catch the three possible exceptions it would throw if it is invalid.

Those are:

• ArgumentNullException
• FormatException
• OverflowException

I have seen some implementations where you can do a regex on the string prior to creating the instance, if you are just trying to validate it and not create it.