code asp.net

CODE LOGIN ..


Imports System.Data.SqlClient
Imports System.Data
Partial Class Default4
Inherits System.Web.UI.Page

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim con As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True")
con.open()

Dim sqlcomm As New SqlCommand("Select * From login where username ='" & TextBox1.Text & "'And password ='" & TextBox2.Text & "'")
sqlcomm.Connection = con

Dim sread As SqlDataReader
sread = sqlcomm.ExecuteReader

If sread.HasRows Then
Session("username") = TextBox1.Text
MsgBox("successful ")
Server.Transfer("Default.aspx")
Else
MsgBox("wrong username and password ")

End If

con.Close()
End Sub


CODE INSERT

Dim con As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True")
con.Open()

Dim co As New SqlCommand("insert into member" & "(name,ic_no,address,phone_numbe)" & "values(@name,@ic_no,@address,@phone_numbe)")

co.Connection = con
co.Parameters.AddWithValue("@name", TextBox1.Text)
co.Parameters.AddWithValue("@ic_no", TextBox2.Text)
co.Parameters.AddWithValue("@address", TextBox3.Text)
co.Parameters.AddWithValue("@phone_numbe", TextBox4.Text)
co.ExecuteScalar()
con.Close()


CODE DELETE

Dim myconnstring As String = "Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=TRUE;User Instance=TRUE"
Dim dbconnection As New SqlConnection(myconnstring)
dbconnection.Open()
Dim SQLString As String
SQLString = "DELETE FROM chart WHERE product_name=@product_name"

Dim DBCommand As New SqlCommand(SQLString)
DBCommand.Connection = dbconnection
DBCommand.Parameters.AddWithValue("@product_name", TextBox1.Text)

DBCommand.ExecuteScalar()
dbconnection.Close()



code update

Dim co As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True")
co.Open()

Dim sqlstring As String
sqlstring = "update member set ic_no=@ic_no,tell_no=@tell_no,address=@address where name=@name"

Dim update As New SqlCommand(sqlstring)
update.Connection = co
update.Parameters.AddWithValue("@name", TextBox1.Text)
update.Parameters.AddWithValue("@ic_no", TextBox2.Text)
update.Parameters.AddWithValue("@tell_no", TextBox3.Text)
update.Parameters.AddWithValue("@address", TextBox4.Text)
update.ExecuteScalar()
update.Clone()