Validate a GUID in C#

Dan Atkinson

8/19/2007 1:32:40 AM #

Why not extend the Guid class and write it thus:

public static class Guid
{
  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);
  public static Boolean IsGuid(String guid)
  {
    if (guid != null)
    {
      if (isGuid.IsMatch(guid))
      {
        return true;
      }
    }
    return false;
  }
}

This way, you could reference the method using the following:

Boolean isValidGuid = Guid.IsGuid("3F2504E0-4F89-11D3-9A0C-0305E82C3301");

Not sure why I mentioned this. Maybe it's because it's nearly 4AM and I'm tired and can't really think logically.

Dan Atkinson

8/19/2007 1:39:12 AM #

Yeah... Hmmm. It is late. Forgot about overwriting the existing Guid class, including its useful functions.

taras

12/24/2007 8:54:26 AM #

My preferred way to deal with Guid is to make it resemble it's value-type counterparts, such as Int32, Enum, etc, which all have <Type>.TryParse(..) in addition to <Type>.Parse(..).

It could lead to something like this:

public static class GuidHelper
{
_public static bool TryParse(object value, out Guid guidValue) {
__bool _result = false;
__try {
___guidValue = Guid.Parse(value);
____result = true;
__} catch {
___guidValue = Guid.Empty;
__}
__return _result;
_}
}

( This could look well more elegant with extension methods in C# 3.5, though i wonder why there's no such standard functionality in place, so one need to resort to exceptions :-\ )

Anuradha Jayasena

6/5/2008 2:51:15 AM #

in that case this might be useful

private bool IsValidGuid(string strGuid)
        {

            bool returnValue = false;
            if (!string.IsNullOrEmpty(strGuid))
            {
                try
                {

                    Guid tmpGuid = new Guid(strGuid);
                    returnValue = true;

                }
                catch (Exception ex)
                {
                                    
                }              

            }

            return returnValue;
        }

I think try-catch is little bit heavy