Function IsNumber C# Exercise - C# Programming Course

Lesson

Functions

Exercise

Function IsNumber

Objetive

Create a function that tells if a string is an intenger number. It should be used like this:

if (IsNumber ("1234"))
System.Console.WriteLine ("It is a numerical value");

Example Code

using System;
public class exercise124
{
    public static bool IsNumber(string text)
    {
        for (int i = 0; i < text.Length; i++)
        if (text[i] < '0') || (text[i] > '9')
            return false;

        return true;
    }


    public static void Main()
    {
        Console.WriteLine( IsNumber("12") );
    }
}

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