Log Example Syntax VB.NET ASP.NET | Log | Source Code
Log Example Syntax VB.NET ASP.NET | Log | Source Code
Summary: – Illustrates using Log with Source Code Syntax Example in VB.NET ASP.NET.
Purpose:
takes a double data type number and returns the natural
(base e) logarithm as a double data type.
Syntax:
Log(doublenumber)
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 Visual Basic to Cut-n-paste code into Log.aspx.vb
Imports System Imports System.IO Imports System.Data Imports System.Math '******************************************************************************** ' 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 Inherits System.Web.UI.Page Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Label1.Text = "Example #1: Log(90)" TextBox1.Text = Log(90) ' Returns 4.49980967033027 Label2.Text = "Example #2: Log(-3.4)" TextBox2.Text = Log(-3.4) ' Returns NaN Not a Number Label3.Text = "Example #3: Log(0)" TextBox3.Text = Log(0) ' Returns -Infinity End Sub End Class |
Step 2: Click on XML to Cut-n-paste code into Log.aspx
< %@ Page Language="VB" AutoEventWireup="false" CodeFile="Log.aspx.vb" 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:
- Install Visual Web Developer 2010
- Install SQL Server Express
- Download Northwind and Pubs Databases
- Attach Northwind Database to Databases in Sql Express
- 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:
|
- Use Visual Web Developer 2010
- Create new web site;
- Click File/New Web Site
- Select ASP.NET Website Template
- Select Visual Basic for Language
- name of Web Site could be VBNET_ASPNET_Syntax.
- Add New folder named “Functions”
- Right-click project name in solution explorer;
- add new folder;
- name of folder could be: Functions
- Add New subfolder named “MathFunctions”
- Right-click Functions folder in solution explorer;
- add new folder;
- name of folder could be: MathFunctions
- 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
- Click on Visual Basic in step 1 at the top of this page to copy code into code-behind Log.aspx.vb
- Click on XML in step 2 above to copy code into web form Log.aspx
- Right-click on Log.aspx in solution explorer and select view in browser
