VB.NET ASP.NET InStr() Source Code Syntax Example

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

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

 *** 1. Download Source Code *** 

VB.NET Syntax StringManipulation InStr download Download Source Code for All VB ASP.NET Examples in One Project – source code for hundreds of VB.NET ASP.NET examples neatly organized in a single project.

 *** 2. InStr Syntax *** 


Purpose:
Returns an integer that represents the position of the first occurrence of
the second string in the first string. The search starts at the specified
position in the string. If the string is not found, the result is 0


Syntax:
InStr(startIndex, stringToSearch, stringToFind)

Parameters Description
startIndex Optional. specifies where to start looking. Zero-based.
stringToSearch Required – string that you want to search
stringToFind Required – string that you are trying to
find into parameter2

Result Data Type Description
string Returns a (zero-based) integer that represents the
position of the first occurrence of the second string in the first
string. The search starts at the specified position in the string.
If the string is not found, the result is 0


 *** 3. InStr – Quick Example *** 

Dim strField1 As String = ” This “
Dim strField2 As String = “is”
TextBox1.Text = InStr(1, strField1, strField2) ‘Returns 4 – spaces are counted

 *** 4. InStr – Full Example *** 

InStr Example Output Screenshot


VB.NET Syntax StringManipulation InStr screenshot


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

Imports System
Imports System.IO
Imports System.Data
 
 
 
 
' This example is from http://idealprogrammer.com
' It shows how you can use InStr syntax in VB.NET ASP.NET
'****************************************************************************************
' Purpose:  Returns an integer that represents the position of the first occurrence of 
' the second string in the first string. The search starts at the specified
' position in the string.  If the string is not found, the result is 0
'
' Syntax: 	InStr(startIndex, stringToSearch, stringToFind)
'
' Parameter1: startIndex - Optional. specifies where to start looking. Zero-based.
'
' Parameter2: stringToSearch - Required - string that you want to search
'
' Parameter3: stringToFind - Required - string that you are trying to 
' find into parameter2
'
' Result: string - Returns a (zero-based) integer that represents the 
' position of the first occurrence of the second string in the first 
' string. The search starts at the specified position in the string. 
' If the string is not found, the result is 0
'
' Quick Example:   Dim strField1 As String = " This "
' Dim strField2 As String = "is"
' TextBox1.Text = InStr(1, strField1, strField2) 'Returns 4 - spaces are counted 
'
'****************************************************************************************
 
Partial Class _InStr
    Inherits System.Web.UI.Page
 
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
 
        Label1.Text = "InStr(startIndex, string1, string2)"
 
        Dim strField1 As String = " This "
        Dim strField2 As String = "is"
 
 
 
 
        TextBox1.Text = Microsoft.VisualBasic.InStr(1, strField1, strField2) 'Returns 4 - spaces are counted
 
 
    End Sub
End Class

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

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