Java validating strings for digits
Explanation \d = only digit allow = length All phone numbers must in “xxx-xxxxxxx” format.
string num String = "1287543"; //"1287543.0" will return false for a long long number1 = 0; bool can Convert = long.
Regular expression pattern in Java always is the best method to validate an user’s phone number.
Here i provide a regex pattern to determines if the phone number is in correct format, the pattern force starting with 3 digits follow by a “-” and 7 digits at the end.
If video does not work, try refreshing the page: All input data is a potential source of problems.
If input is not checked to verify that it has the correct type, format, and length, it can cause problems.
Try Parse(num String, out number3); if (can Convert == true) Console.
Write Line("number3 now = ", number3); else Console.
It’s the most easy way to determine if the String represents a valid number.Generally, this input will be of a specific type: for example, a user interface that requests a person’s name expects a series of alphabetic characters.If programs are not carefully written, attackers can construct inputs that can cause malicious code to be executed.Please visit OWASP Validation Regex Repository for other useful regex's. Creating custom constraints is beyond the scope of this guide.
Reference Model Data Type: Big Decimal, Big Integer, Char Sequence, byte, short, int, long and the respective wrappers of the primitive types; Additionally supported by HV: any sub-type of Number Use: Checks whether the annotated value is a number having up to integer digits and fraction fractional digits Reference Model Data Type:
How can I check if one string contains another substring?