How to validate a valid GUID Value in C#

May 20, 2005 · 1 min read

In this implementation  you pass in a Guid as an 'out' parameter along with the string you want to test - it then fills in the Guid and returns true / false depending on whether the Guid was valid...

private static Regex isGuid = new Regex(@"^(\{){0,1}[0-9a-fA-F]{8}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{12}(\}){0,1}$", RegexOptions.Compiled);

                                    internal static bool IsGuid(string candidate, out Guid output)

                                    {

                                                bool isValid = false;

                                                output=Guid.Empty;

                                                if(candidate!=null)

                                                {

                                                            if (isGuid.IsMatch(candidate))

                                                            {

                                                                        output=new Guid(candidate);

                                                                        isValid = true;

                                                            }

                                                }

                                                return isValid;

                                    }

This is very useful in other Microsoft Products like Microsof Content Management Server/SharePoint  where you use GUID quite frequently in the API Calls.

This article is part of the GWB Archives. Original Author: Jawad Khan

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