What is wrong in this code Vb MySql data to TextBox - mysql

Question

What is wrong in this code
I run the software click the button and nothing happens if you have a better code that would help thanks in advance
Dim sql As String
Dim con As MySqlConnection = New
MySqlConnection("Server=localhost;Database=******;Uid=*****;password =******")
Dim ds As DataSet = New DataSet
Dim dataadapter As MySqlDataAdapter = New MySqlDataAdapter
Dim cmd As MySqlCommand = New MySqlCommand()
Dim datareader As MySqlDataReader
Try
sql = "SELECT * FROM users"
con.Open()
cmd.CommandText = sql
cmd.Connection = con
dataadapter.SelectCommand = cmd
datareader = cmd.ExecuteReader
While datareader.Read
datareader.Read()
Email.Text = datareader("Email")
LastName.Text = datareader("LastName")
Address.Text = datareader("Address")
End While
Catch ex As Exception
End Try
con.Close()
End Sub

Answer 1

Narrow the scope of your select. The way its written I think it might set the textbox 100 times if 100 results are returned. Here is how I would write this:
Imports MySql.Data.MySqlClient
Public Sub getData()
Dim objConn As MySqlConnection = New MySqlConnection("Data Source=localhost;" _
& "Database=TestDB;" _
& "User ID=Root;" _
& "Password=myPassword;")
Dim strSQL As String = "SELECT TOP 1 Email, LastName, Address FROM users"
Dim da As MySql.Data.MySqlClient.MySqlDataAdapter
Dim dt As New DataTable
Try
objConn.Open()
da = New MySql.Data.MySqlClient.MySqlDataAdapter(strSQL, objConn)
da.Fill(dt)
If dt.Rows.Count > 0 Then
Email.Text = dt.Rows(0)("Email").ToString
LastName.Text = dt.Rows(0)("LastName").ToString
Address.Text = dt.Rows(0)("Address").ToString
End If
da = Nothing
objConn.Close()
objConn = Nothing
Catch ex As Exception
objConn.Close()
objConn = Nothing
End Try
End Sub