Round Example Syntax VB.NET ASP.NET | Round | Source Code

Round Example Syntax VB.NET ASP.NET | Round | Source Code

Summary: – Illustrates using with in VB.NET ASP.NET.



Purpose:
takes a decimal or double as input parameter1
and returns the number rounded to the specified number
of fractional decimals. If parameter 2 is not used,
result is rounded to whole number. Parameter3 specifies
rounding mode

Syntax:
1. Round(decimal)
2. Round(decimal, int32)
3. Round(decimal, mode)
4. Round(decimal, int32, mode)
5. Round(double)
6. Round(double, int32)
7. Round(double, mode)
8. Round(double, int32, mode)

Parameters Description
decimal Any valid System.Decimal data type number
double – any valid System.Double data type.
Parameter1 specifies the number to be rounded
int32 or mode 1. int32 specifies the number of fractional
digits to be returned in the result. If
there is no parameter2 or if it is mode,
the result is rounded to a whole number.
2. mode – The mode parameter controls how
value is rounded if the first decimal
digit in value is 5
mode The mode parameter controls how value
is rounded if the first decimal digit in value is 5
There are two possible modes:
1. MidpointRounding.ToEven. If the ones digit
is odd, it is changed to an even digit.
Otherwise, it is left unchanged. This is
often called rounding to nearest, or bankers
rounding. It minimizes rounding errors that
result from consistently rounding a midpoint
value in a single direction.
2. MidpointRounding.AwayFromZero. The
ones digit is always rounded up to the
next digit. This is the most popular
rounding method.

Result Data Type Description
decimal or double depends on data type
of parameter1. It is decimal, if parameter1 is
decimal. If parameter1 is double, result is double.

Quick Example
Round(3.5) ‘ Returns 4

Step 1: Click on Visual Basic to Cut-n-paste code into Round.aspx.vb

 
Imports System
Imports System.IO
Imports System.Data
Imports System.Math
 
'********************************************************************************
' Purpose: takes a decimal or double as input parameter1
' and returns the number rounded to the specified number
' of fractional decimals. If parameter 2 is not used,
' result is rounded to whole number. Parameter3 specifies
' rounding mode
'
' Syntax: 	1. Round(decimal)
' 2. Round(decimal, int32)
' 3. Round(decimal, mode)
' 4. Round(decimal, int32, mode)
' 5. Round(double)
' 6. Round(double, int32)
' 7. Round(double, mode)
' 8. Round(double, int32, mode)
'
' Parameter1: decimal - Any valid System.Decimal data type number
' double - any valid System.Double data type.
' Parameter1 specifies the number to be rounded
'
' Parameter2: int32 or mode - 1. int32 specifies the number of fractional
' digits to be returned in the result. If
' there is no parameter2 or if it is mode,
' the result is rounded to a whole number.
' 2. mode - The mode parameter controls how
' value is rounded if the first decimal
' digit in value is 5
'
' Parameter3: mode - The mode parameter controls how value
' is rounded if the first decimal digit in value is 5
' There are two possible modes:
' 1. MidpointRounding.ToEven. If the one's digit
' is odd, it is changed to an even digit.
' Otherwise, it is left unchanged. This is
' often called rounding to nearest, or banker's
' rounding. It minimizes rounding errors that
' result from consistently rounding a midpoint
' value in a single direction.
' 2. MidpointRounding.AwayFromZero. The
' one's digit is always rounded up to the
' next digit.  This is the most popular
' rounding method.
'
' Result: decimal or double - depends on data type
' of parameter1. It is decimal, if parameter1 is
' decimal. If parameter1 is double, result is double.
'
' Quick Example: Round(3.5) ' Returns 4
'
'********************************************************************************
' This example is from http://idealprogrammer.com
 
 
 
Partial Class _Round
    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: 	Round(decimal)"
 
        TextBox1.Text = String.Format("Round(3.5) = {0}", Round(3.5)) ' Returns 4
 
 
        Label2.Text = "Example #2: 	Round(double, mode)"
        Dim myDouble As Double = 6.5
        TextBox2.Text = String.Format("Round(myDouble, MidpointRounding.ToEven) = {0}", _
  Round(myDouble, MidpointRounding.ToEven)) ' Returns 6
 
        Label3.Text = "Example #3: 	Round(double, mode)"
 
 
 
        TextBox3.Text = String.Format("Round(myDouble, MidpointRounding.AwayFromZero) = {0}", _
         Round(myDouble, MidpointRounding.AwayFromZero)) ' Returns 7
 
    End Sub
End Class

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

< %@ Page Language="VB" AutoEventWireup="false" CodeFile="Round.aspx.vb" Inherits="_Round" %>
 
< !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:

VB.NET ASP.NET Syntax Functions MathFunctions Round
  1. Use Visual Web Developer 2010
  2. 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.
  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 Round 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 Round
  6. Click on Visual Basic in step 1 at the top of this page to copy code into code-behind Round.aspx.vb
  7. Click on XML in step 2 above to copy code into web form Round.aspx
  8. Right-click on Round.aspx in solution explorer and select view in browser