Mobile Number validation Using Python

If you’re working on a Python project and want to add a mobile number validation feature, you should follow some validation criteria.

Mobile Number Validation Criteria:

The mobile number should only have 10 digits.
The mobile number should only begin with 7, 8, or 9 digits.
There should be no characters or strings in the mobile number.

All of the criteria listed above must be met in order to validate a mobile number.

NOTE: Here, we used the Indian mobile number validation requirements. You can easily edit the code to fit your country’s criteria.

We can Validate a mobile number using two methods:

Using If-Else conditional statements.
Using Regex

Mobile Number validation Using Python

Below are the ways to validate the given mobile number using python:

Using If-Else conditional statements
Using Regex Module

Method #1: Using If-Else conditional statements

Approach:

Give some random 10 digit mobile number as user input using the input() function and store it in a variable.
Check if the length of the given mobile number is greater than or less than 10 using the if conditional statement
If it is true then print “Invalid Mobile number. Mobile number must have 10 digits”
Else Check if the first digit of the given mobile number is 7 or 8 or 9 using the if conditional statement.
Handling the errors using the try-except blocks.
If it is true, then convert the given mobile number to an Integer using the int() function and store it in the same variable.
Print the given mobile number is a valid number
Print “Invalid Mobile number. Mobile number must not contain any characters”
Else print “Invalid Mobile number. Mobile number must begin with 7 or 8 or 9”.
The Exit of the Program.

Below is the implementation:

# Give some random 10 digit mobile number as user input using the input() 
# function and store it in a variable.
gvn_mobilenumb = input("Enter some random 10 digit mobile number = ")

# Check if the length of the given mobile number is greater than or less than 10
# using the if conditional statement
if len(gvn_mobilenumb) > 10 or len(gvn_mobilenumb) < 10:
    # If it is true then print "Invalid Mobile number. Mobile number must have 10 digits"
    print("Invalid Mobile number. Mobile number must have 10 digits")
else:
    # Else Check if first digit of the given mobile number is 7 or 8 or 9 using the if conditional statement
    if gvn_mobilenumb[0] == '7' or gvn_mobilenumb[0] == '8' or gvn_mobilenumb[0] == '9':
        # Handling the errors using the try-except blocks
        try:
            # If it is true, then convert the given mobile number to an Integer using the
            # int() function and store it in the same variable.
            gvn_mobilenumb = int(gvn_mobilenumb)
            # Print the given mobile number is a valid number
            print("The given mobile number is a Valid Number")
        except:
            # Print "Invalid Mobile number. Mobile number must not contain any characters"
            print('Invalid Mobile number. Mobile number must not contain any characters')
    else:
        # Else print "Invalid Mobile number. Mobile number must begin with 7 or 8 or 9"
        print("Invalid Mobile number. Mobile number must begin with 7 or 8 or 9")

Output:

Enter some random 10 digit mobile number = 9989593198
The given mobile number is a Valid Number

Enter some random 10 digit mobile number = 4567890182
Invalid Mobile number. Mobile number must begin with 7 or 8 or 9

Enter some random 10 digit mobile number = 9989583v99
Invalid Mobile number. Mobile number must not contain any characters

Method #2: Using Regex Module

fullmatch() function:

fullmatch() is a function that accepts two inputs: pattern and the string for validation.

If and only if the full string matches the pattern, it returns a match object; otherwise, it returns None.
We can determine whether or not the return value is a valid number based on the return value.

Mobile Number Validation Criteria:

The first digit should have values ranging from 6 to 9.
The remaining 9 numbers might be any integer between 0 and 9.

Example Pattern:

‘[6-9][0-9]{9}’: It means the starting should be between 6 to 9 and the next nine digits can be any number between 0 and 9.

‘[6-9] [0-9] [0-9] [0-9] [0-9] [0-9] [0-9] [0-9] [0-9] [0-9]’: This pattern works in the same way as the above one.

Approach:

Import re(regex) module using the import keyword
Give some random mobile number as user input using the input() function and store it in a variable.
Pass the Pattern, given mobile number as arguments to the fullmatch() function to check if the entire
mobile number matches the pattern else it returns None.
Store it in a variable
Here the pattern represents that the starting number should be between 6-9 and the next nine digits can be any number between 0 and 9.
Check if the above result is not Equal to None Using the if conditional statement
If it is true, i.e the output is Not None then print “Valid Number”
Else print “Invalid Number”.
The Exit of the Program.

Below is the implementation:

# Import re(regex) module using the import keyword
import re
# Give some random mobile number as user input using the input() 
# function and store it in a variable.
gvn_mobilenumb = input("Enter some random mobile number = ")
# Pass the Pattern, given mobile number as arguments to the fullmatch() function to 
# check if the entire mobile number matches the pattern else it returns None.
# Store it in a variable
# Here the pattern represents that the starting number should be between 6-9
# and the next nine digits can be any number between 0 and 9.
rslt = re.fullmatch('[6-9][0-9]{9}',gvn_mobilenumb) 
# Check if the above result is not Equal to None Using the if conditional statement
if rslt!=None: 
     # If it is true, i.e the output is not None then print "Valid Number"
     print('The given mobile number is a Valid Number')
else:
     # Else print "Invalid Number"
     print('The given mobile number is Invalid')

Output:

Enter some random mobile number = 9494580181
The given mobile number is a Valid Number