如何判断字符串是否为GUID格式

转自：http://blog.sina.com.cn/s/blog_3fa7f1a60100sk6h.html

个人感觉正则表达式效率要好些，异常方式有些耗费性能。

异常判断
static bool IsGuidByError(string strSrc)

        {

            if (String.IsNullOrEmpty(strSrc)) { return false; }

            bool _result = false;

            try

            {

                Guid _t = new Guid(strSrc);

                _result = true;

            }

            catch { }

            return _result;

        }
 
 
正则表达式
static bool IsGuidByReg(string strSrc)

        {

            Regex reg = new Regex("^[A-F0-9]{8}(-[A-F0-9]{4}){3}-[A-F0-9]{12}$", RegexOptions.Compiled);

            return reg.IsMatch(strSrc);

        }
 
 
字符数组(不够严谨)
static bool IsGuidByArr(string strSrc)

        {

            if (String.IsNullOrEmpty(strSrc) || strSrc.Length!=36) { return false; }

            string[] arr = strSrc.Split("-");

            if (arr.Length != 5) { return false; }

            for (int i = 0; i < arr.Length; i++)

            {

                for (int j = 0; j < arr[i].Length; j++)

                {

                    char a = arr[i][j];

                    if (!((a >= 48 && a< = 57) || (a >= 65&& a <= 90) || (a> = 97 && a< = 122)))

                    {

                        return false;

                    }

                }

            }

            return true;

        }
 
 
考虑到正则表达式不编译的情况
static bool IsGuidByRegNoComplied(string strSrc)

        {

            Regex reg = new Regex("^[A-F0-9]{8}(-[A-F0-9]{4}){3}-[A-F0-9]{12}$");

            return reg.IsMatch(strSrc);

        }
 
 
Guid的TryParse/Parse方法(.Net 4.0才新增加的)
 
static bool IsGuidByParse(string strSrc)

        {

            Guid g = Guid.Empty;

            return Guid.TryParse(strSrc, out g);

        }