Dataset Textbox Integration
Posted: Sun 20 Mar 2005 04:56
I am very new to all this and hope someone can help me. I am sure I am doing something stupid but I have spent many hours reading to figure out what I am doing wrong and realize I need help.
All I want to do is load data into a bunch of text fields on the screen based on loginID and let users update them back to the database.
I created a simple ASPX page to demonstate my issue and copied it below:
Code: Select all
Imports CoreLab.MySql
Imports System.Data
Public Class test
Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
Private Sub InitializeComponent()
End Sub
Protected WithEvents myGrid As System.Web.UI.WebControls.DataGrid
Protected WithEvents txTest1 As System.Web.UI.WebControls.TextBox
Protected WithEvents txTest2 As System.Web.UI.WebControls.TextBox
'NOTE: The following placeholder declaration is required by the Web Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclaration As System.Object
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here
Dim MyDS As New DataSet
Dim connStr As String
Dim SQL As String
connStr = "User Id=test;Password=test;Host=localhost;Database=test;"
SQL = "SELECT CompanyName FROM company where companyID = 1"
Dim conn As MySqlConnection = New MySqlConnection(connStr)
Dim Adapter As New MySqlDataAdapter(SQL, connStr)
Adapter.Fill(MyDS)
myGrid.DataSource = MyDS
myGrid.DataBind()
Dim myTable As DataTable
Dim myRow As DataRow
Dim myCol As DataColumn
Me.txTest1.Text = myRow.Item(1) '---------------- errors out
Me.txTest2.Text = myRow("CompanyName") '---------------- errors out
End Sub
End Class
When I run the code I get the error below. I know the dataset is loading properly as it shows up in the Datagrid Properly if I remove the offending statements.
Code: Select all
Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:
Line 47: Dim myRow As DataRow
Line 48: Dim myCol As DataColumn
Line 49: Me.txTest1.Text = myRow.Item(1) '---------------- errors out
Line 50: Me.txTest2.Text = myRow("CompanyName") '---------------- errors out
Line 51: End Sub
Source File: c:\inetpub\wwwroot\test\test.aspx.vb Line: 49
Stack Trace:
[NullReferenceException: Object reference not set to an instance of an object.]
eFraud.test.Page_Load(Object sender, EventArgs e) in c:\inetpub\wwwroot\test\test.aspx.vb:49
System.Web.UI.Control.OnLoad(EventArgs e)
System.Web.UI.Control.LoadRecursive()
System.Web.UI.Page.ProcessRequestMain()
Many thanks for your help!!