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

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

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



Purpose:
takes a double data type number and returns the natural
(base e) logarithm as a double data type.

Syntax:
Log(doublenumber)

Parameters Description
doublenumber Any valid System.Double data type number
1. Positive – returns natural logarithm
2. Zero – returns -Infinity
3. Negative – returns NaN (Not a Number)

Result Data Type Description
double the natural (base e) logarithm

Quick Example
Log(90) // Returns 4.49980967033027

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

using System;
using System.IO;
using System.Data;
 
//********************************************************************************
// Purpose: takes a double data type number and returns the natural
// (base e) logarithm as a double data type.
//
//
// Syntax: 	Log(doublenumber)
//
// Parameter1: doublenumber - Any valid System.Double data type number
// 1. Positive - returns natural logarithm
// 2. Zero - returns -Infinity
// 3. Negative - returns NaN (Not a Number)
//
// Result: double - the natural (base e) logarithm
//
// Quick Example: Log(90) // Returns 4.49980967033027
//
//********************************************************************************
// This example is from http://idealprogrammer.com
 
 
 
partial class _Log : System.Web.UI.Page
{
 
    protected void Page_Load(object sender, System.EventArgs e)
    {
 
 
        Label1.Text = "Example #1: 	Log(90)";
 
 
        TextBox1.Text = Math.Log(90).ToString(); // Returns 4.49980967033027
 
 
        Label2.Text = "Example #2: 	Log(-3.4)";
 
 
        TextBox2.Text = Math.Log(-3.4).ToString(); // Returns NaN Not a Number
 
 
        Label3.Text = "Example #3: 	Log(0)";
 
 
 
 
        TextBox3.Text = Math.Log(0).ToString(); // Returns -Infinity
 
 
    }
 
 
}

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

< %@ Page Language="VB" AutoEventWireup="false" CodeFile="Log.aspx.cs" Inherits="_Log" %>
 
< !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 MathFunctions Log
  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 “MathFunctions”
    • Right-click Functions folder in solution explorer;
    • add new folder;
    • name of folder could be: MathFunctions
  5. Add Web Form Named Log to MathFunctions folder
    • Right-click MathFunctions folder;
    • add new item;
    • Select Web Form
    • Check place code behind in separate file
    • Web Form name could be Log
  6. Click on cs in step 1 at the top of this page to copy code into code-behind Log.aspx.cs
  7. Click on XML in step 2 above to copy code into web form Log.aspx
  8. Right-click on Log.aspx in solution explorer and select view in browser