Question

I need to validate the just the format of the entered string for Latitude and Longitude and not if its a correct value for Latitude or Longitude.

The format Latitude 89:90:00N or 67:90:76 S and for Longitude 67:23:00E or 78:23:45W

I am using the below expression for which I am getting a false

 if (!Regex.IsMatch(currentValue, "^[0-9][0-9]:[0-9][0-9]:[0-9][0-9][N][S]$"))

                                Errors.Text = "Invalid format of Latitude;

Please correct me where am I going wrong..I need to validate if its either N or S (without case sensitivity).

Answer 1

You have made both N and S mandatory.

"^(?:90|[0-8][0-9]):[0-5][0-9]:[0-5][0-9][NS]$"    // latitude
"^(?:180|1[0-7][0-9]|[0-9][0-9]):[0-5][0-9]:[0-5][0-9][EW]$"  // longitude

should work. This will also reject invalid entries like 190:67:75E or 99:99:99S.