ConvertToDouble Example Syntax C-Sharp ASP.NET | C# ConvertToDouble | Source Code

ConvertToDouble Example Syntax C-Sharp ASP.NET | C# ConvertToDouble | Source Code

Summary: – Illustrates using with in C-Sharp ASP.NET.



Purpose:
Converts positive and negative numbers into double data type

Syntax:
Convert.ToDouble(expression)

Parameters Description
expression -1.79769313486231570E+308 through
-4.94065645841246544E-324 for negative values;
4.94065645841246544E-324 through
1.79769313486231570E+308 for positive values.

Result Data Type Description
double double precision floating point number

Quick Example
Dim double1 As Double = Convert.ToDouble(1.33)
TextBox1.Text = double1 Returns 1.33

Step 1: Click on cs to Cut-n-paste code into ConvertToDouble.aspx.cs

using System;
using System.IO;
using System.Data;
 
//****************************************************************************************
// Purpose: Converts positive and negative numbers into double data type
//
// Syntax: Convert.ToDouble(expression)
//
// Parameter1: expression - -1.79769313486231570E+308 through 
// -4.94065645841246544E-324 for negative values; 
// 4.94065645841246544E-324 through 
// 1.79769313486231570E+308 for positive values.
//
// Result: double - double precision floating point number
//
// Quick Example:   Dim double1 As Double = Convert.ToDouble(1.33)
//       TextBox1.Text = double1 // Returns 1.33
//
//
//****************************************************************************************
// This example is from http://idealprogrammer.com
// It shows how you can use CDbl syntax in C-Sharp ASP.NET
 
 
partial class _ConvertToDouble : System.Web.UI.Page
{
 
    protected void Page_Load(object sender, System.EventArgs e)
    {
 
        Label1.Text = "Example #1: 	Convert.ToDouble(1.33) ";
 
        double double1 = Convert.ToDouble(1.33);
 
        TextBox1.Text = double1.ToString(); // Returns 1.33
 
        Label2.Text = "Example #2: 	Convert.ToDouble(-3.4) ";
 
        double Double2 = Convert.ToDouble(-3.4);
 
        TextBox2.Text = Double2.ToString(); // Returns -3.4
 
        Label3.Text = "Example #3: 	Convert.ToDouble(5)";
 
        double Double3 = Convert.ToDouble(5);
 
        TextBox3.Text = Double3.ToString(); // Returns 5
 
 
    }
 
 
}

Step 2: Click on XML to Cut-n-paste code into ConvertToDouble.aspx

< %@ Page Language="VB" AutoEventWireup="false" CodeFile="ConvertToDouble.aspx.cs" Inherits="_ConvertToDouble" %>
 
< !DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h1><asp:label ID="Label1" runat="server" Text="Label"></asp:label> </h1>
         <asp:textbox ID="TextBox1" runat="server"></asp:textbox><br />
          <h1><asp:label ID="Label2" runat="server" Text="Label"></asp:label> </h1>
         <asp:textbox ID="TextBox2" runat="server"></asp:textbox><br />
          <h1><asp:label ID="Label3" runat="server" Text="Label"></asp:label> </h1>
         <asp:textbox ID="TextBox3" runat="server"></asp:textbox><br />
 
 
 
    </div>
    </form>
</body>
</html>

Prerequistes:

  1. Install Visual Web Developer 2010
  2. Install SQL Server Express
  3. Download Northwind and Pubs Databases
  4. Attach Northwind Database to Databases in Sql Express
  5. Attach pubs Database to Databases in Sql Express

Notes:

  • You can build your own library of syntax examples by using same web site over and over and just add new web forms to it.

Instructions:

C-Sharp ASP.NET Syntax Functions ConversionFunctions ConvertToDouble
  1. Use Visual Web Developer 2010
  2. Create new web site;
    • Click File/New Web Site
    • Select ASP.NET Website Template
    • Select C-Sharp for Language
    • name of Web Site could be CSharp_ASPNET_Syntax.
  3. Add New folder named “Functions”
    • Right-click project name in solution explorer;
    • add new folder;
    • name of folder could be: Functions
  4. Add New subfolder named “ConversionFunctions”
    • Right-click Functions folder in solution explorer;
    • add new folder;
    • name of folder could be: ConversionFunctions
  5. Add New subfolder named “TypeConversionFunctions”
    • Right-click Functions folder in solution explorer;
    • add new folder;
    • name of folder could be: TypeConversionFunctions
  6. Add Web Form Named ConvertToDouble to TypeConversionFunctions folder
    • Right-click TypeConversionFunctions folder;
    • add new item;
    • Select Web Form
    • Check place code behind in separate file
    • Web Form name could be ConvertToDouble
  7. Click on cs in step 1 at the top of this page to copy code into code-behind ConvertToDouble.aspx.cs
  8. Click on XML in step 2 above to copy code into web form ConvertToDouble.aspx
  9. Right-click on ConvertToDouble.aspx in solution explorer and select view in browser