Super Regular Expression validation Date and Time

Regular Expressions play an important role in verification. The following are my regular functions for verifying the time:

Public   Bool Mytime ( String Str)
{
Bool Flag = False ;
String RegEx =   @" ^ (\ D {2} ([02468] [048]) | ([13579] [26]) [\-\/\ s]? (0? [13578]
) | (1 [02]) [\-\/\ s]? (0? [1-9]) | ([1-2] [0-9]) | (3 [01]) | (0? [4
69]) | (11) [\-\/\ s]? (0? [1-9]) | ([1-2] [0-9]) | (30) | (0? 2 [\-\/\
S]? (0? [1-9]) | ([1-2] [0-9]) | (\ D {2} ([02468] [1235679]) | ([1
3579] [01345789]) [\-\/\ s]? (0? [13578]) | (1 [02]) [\-\/\ s]? ((
0? [1-9]) | ([1-2] [0-9]) | (3 [01]) | (0? [469]) | (11) [\-\/\ s]? ((
0? [1-9]) | ([1-2] [0-9]) | (30) | (0? 2 [\-\/\ s]? (0? [1-9]) | (1 [0-9]
) | (2 [0-8]) " ; // Date
RegEx + =   @" (\ S (0? [0-9]) | ([1-2] [0-3]) \ :( [0-5]? [0-9]) (\ s) | (\ :( [0-5]? [0-9])? $ " ; // Time part
Regexoptions options = (Regexoptions. ignorepatternwhitespace | Regexoptions. multiline) | Regexoptions. ignorecase );
RegEx Reg =   New RegEx (RegEx, options );
If (Reg. ismatch (STR ))
{
Flag=True;
}
Return Flag;
}

The regular expression can accurately verify whether the entered time is correct and verify the leap year.