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to Phone Number in the C# Track

Published at Nov 15 2019 · 0 comments
Instructions
Test suite
Solution

Clean up user-entered phone numbers so that they can be sent SMS messages.

The North American Numbering Plan (NANP) is a telephone numbering system used by many countries in North America like the United States, Canada or Bermuda. All NANP-countries share the same international country code: 1.

NANP numbers are ten-digit numbers consisting of a three-digit Numbering Plan Area code, commonly known as area code, followed by a seven-digit local number. The first three digits of the local number represent the exchange code, followed by the unique four-digit number which is the subscriber number.

The format is usually represented as

(NXX)-NXX-XXXX

where N is any digit from 2 through 9 and X is any digit from 0 through 9.

Your task is to clean up differently formatted telephone numbers by removing punctuation and the country code (1) if present.

For example, the inputs

  • +1 (613)-995-0253
  • 613-995-0253
  • 1 613 995 0253
  • 613.995.0253

should all produce the output

6139950253

Note: As this exercise only deals with telephone numbers used in NANP-countries, only 1 is considered a valid country code.

Running the tests

To run the tests, run the command dotnet test from within the exercise directory.

Initially, only the first test will be enabled. This is to encourage you to solve the exercise one step at a time. Once you get the first test passing, remove the Skip property from the next test and work on getting that test passing. Once none of the tests are skipped and they are all passing, you can submit your solution using exercism submit PhoneNumber.cs

Further information

For more detailed information about the C# track, including how to get help if you're having trouble, please visit the exercism.io C# language page.

Source

Event Manager by JumpstartLab http://tutorials.jumpstartlab.com/projects/eventmanager.html

PhoneNumberTest.cs

// This file was auto-generated based on version 1.7.0 of the canonical data.

using System;
using Xunit;

public class PhoneNumberTest
{
    [Fact]
    public void Cleans_the_number()
    {
        var phrase = "(223) 456-7890";
        Assert.Equal("2234567890", PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Cleans_numbers_with_dots()
    {
        var phrase = "223.456.7890";
        Assert.Equal("2234567890", PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Cleans_numbers_with_multiple_spaces()
    {
        var phrase = "223 456   7890   ";
        Assert.Equal("2234567890", PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_when_9_digits()
    {
        var phrase = "123456789";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_when_11_digits_does_not_start_with_a_1()
    {
        var phrase = "22234567890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Valid_when_11_digits_and_starting_with_1()
    {
        var phrase = "12234567890";
        Assert.Equal("2234567890", PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Valid_when_11_digits_and_starting_with_1_even_with_punctuation()
    {
        var phrase = "+1 (223) 456-7890";
        Assert.Equal("2234567890", PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_when_more_than_11_digits()
    {
        var phrase = "321234567890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_with_letters()
    {
        var phrase = "123-abc-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_with_punctuations()
    {
        var phrase = "123-@:!-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_area_code_starts_with_0()
    {
        var phrase = "(023) 456-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_area_code_starts_with_1()
    {
        var phrase = "(123) 456-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_exchange_code_starts_with_0()
    {
        var phrase = "(223) 056-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_exchange_code_starts_with_1()
    {
        var phrase = "(223) 156-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_area_code_starts_with_0_on_valid_11_digit_number()
    {
        var phrase = "1 (023) 456-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_area_code_starts_with_1_on_valid_11_digit_number()
    {
        var phrase = "1 (123) 456-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_exchange_code_starts_with_0_on_valid_11_digit_number()
    {
        var phrase = "1 (223) 056-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }

    [Fact(Skip = "Remove to run test")]
    public void Invalid_if_exchange_code_starts_with_1_on_valid_11_digit_number()
    {
        var phrase = "1 (223) 156-7890";
        Assert.Throws<ArgumentException>(() => PhoneNumber.Clean(phrase));
    }
}
using System;
using System.Text;
using System.Text.RegularExpressions;

public class PhoneNumber
{
    public static string Clean(string phoneNumber) {
        var tel = new StringBuilder();
        phoneNumber = phoneNumber.Trim();
        if(phoneNumber[0] == '+') phoneNumber = phoneNumber.Substring(1);
        if(phoneNumber[0] == '1') phoneNumber = phoneNumber.Substring(1);
        foreach(var ch in phoneNumber){
            if(ch >= '0' && ch <='9')
            {
                if(ch < '2' &&(tel.Length == 0 || tel.Length == 3))
                     throw new ArgumentException("Invalid phonenumber");
                else tel.Append(ch);
            }else if(" .-()".Contains(ch) && (tel.Length%3 == 0))
            {
                continue;
            }else
            {
                throw new ArgumentException("Invalid characters in string");
            }
        }
        if(tel.Length == 10)
            return tel.ToString();
        else
            throw new ArgumentException("Phonnumber has wrong length");
    }
}

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