C# IsNumeric Example Syntax | C-Sharp IsNumeric | Source Code

C# IsNumeric Example Syntax | C-Sharp IsNumeric | Source Code

Purpose: – Illustrates the for .




Step 1: Click on C# to Cut-n-paste code into clsIsNumeric.cs

using System;
public class clsIsNumeric
{
 
    public void Main()
    {
 
        //****************************************************************************************
        // Example #1: IsNumeric(string)
 
        //****************************************************************************************
 
 
        //****************************************************************************************
        // Example #1: IsNumeric(string)
        // Not supported in C#, but here is code that duplicates what happens in VB
        // Returns a Boolean value that indicates if the string is Numeric. 
        //****************************************************************************************
 
        Console.WriteLine("Example #1: IsNumeric(strField)");
 
        string strField = "100.00";
 
        Console.WriteLine(SimulateIsNumeric.IsNumeric(strField)); //Returns True - decimals are numeric
 
        //write blank line to make output easier to read
        Console.WriteLine();
 
 
 
        //Prevent console from closing before you press enter
        Console.ReadLine();
 
    }
 
 
}
//----------------------------------------------------------------------------------------
//	Copyright © 2003 - 2011 Tangible Software Solutions Inc.
//	This class can be used by anyone provided that the copyright notice remains intact.
//
//	This class simulates the behavior of the classic VB 'IsNumeric' function.
//----------------------------------------------------------------------------------------
public static class SimulateIsNumeric
{
    public static bool IsNumeric(object expression)
    {
        if (expression == null)
            return false;
 
        double testDouble;
        if (double.TryParse(expression.ToString(), out testDouble))
            return true;
 
        //VB's 'IsNumeric' returns true for any boolean value:
        bool testBool;
        if (bool.TryParse(expression.ToString(), out testBool))
            return true;
 
        return false;
    }
}

Step 2: Click on C# to Cut-n-paste code into Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace CSharp_Syntax
{
    class Program
    {
        static void Main(string[] args)
        {
 
 
            clsIsNumeric myIsNumeric = new clsIsNumeric();
            myIsNumeric.Main();
 
        }
    }
}

Prerequistes:

  1. Install C# (Express or Standard Edition)
  2. Install SQL Server Express
  3. Download Northwind and pubs Database
  4. Attach Northwind Database to Databases in Sql Express
  5. Attach pubs Database to Databases in Sql Express

Notes:

  • Console Application is used to simplify things, but Windows Forms or Web Forms could also be used
  • You can build a library of syntax examples by using same project over and over and just commenting out what you do not want to execute in Program.cs

IsNumericuctions:

  1. Use C# 2010 Express or Standard Edition
  2. Create new project;
    • Click File/New Project
    • Select Console Application Template
    • Select C# for Language
    • name of project could be CSharp_Syntax.
  3. CS Syntax File Directory Binary File Read Sequential

  4. Add New folder named “StringManipulation”
    • Right-click project name in solution explorer;
    • add new folder;
    • name of folder could be: StringManipulation
  5. Add Class Named clsIsNumeric to StringManipulation folder
    • Right-click StringManipulation folder;
    • add new item;
    • Select class
    • Class name could be clsIsNumeric
  6. Click on C# in code in step 1 at top of page to copy code into clsIsNumeric.cs
  7. Click on C# in step 2 at top of page to copy code into Program.cs
  8. Click green arrow or press F5 to run program