Comments on: Accessing MySQL on VB.NET using MySQL Connector/Net, Part VIII: Display Result on GUI

By: linglom

linglom — Mon, 07 Jun 2010 03:53:59 +0000

Hi, Dipta
You are a good observer. This post was added to the series later. And my testing environment has changed so I’ve added another connection string to make the code work.
For the second question, I have comment out those codes which are added on the previous part because I want you to see only the result from this part.

Hi, Sabuj and Dipta
Can you show more detail of the error message?

By: linglom fan

linglom fan — Thu, 27 May 2010 07:18:08 +0000

…please help me, i have a big problem…urgent!!!

By: sabuj and dipta

sabuj and dipta — Fri, 21 May 2010 05:50:07 +0000

HELLO SIR;
i am using mysql sever 5.1 and visual studio 2010 express edition n working on VB
i stucked to a problem at the stage of “Retrieve data from database”
i.e
Imports MySql.Data.MySqlClient

Public Class Form1

Private connStr As String = “Database=abc;” & _
“Data Source=169.254.248.27;” & _
“User Id=sd;Password=123;” & _
“Connection Timeout=20″

Private Sub Form1_Load(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles MyBase.Load

retriveData()

End Sub

Public Sub retriveData()
Try
Dim query As String = “SELECT * FROM stock_sale”
Dim connection As New MySqlConnection(connStr)
Dim cmd As New MySqlCommand(query, connection)

connection.Open()

Dim reader As MySqlDataReader
reader = cmd.ExecuteReader()

While reader.Read()
Console.WriteLine((reader.GetString(0) & “, ” & _
reader.GetString(1)))
End While

reader.Close()
connection.Close()
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
End Sub
End Class

after doing all these the output is not showing according to you
it’s showing:

A first chance exception of type ‘MySql.Data.MySqlClient.MySqlException’ occurred in MySql.Data.dll
A first chance exception of type ‘MySql.Data.MySqlClient.MySqlException’ occurred in MySql.Data.dll

After running the code it’s not retrieving data from the Mysql server where i had created a directory “abc” and table “stock_sale”.

PLZZZZ SIR HELP US OUT AS WE R BEGINNERS !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

By: Dipta

Dipta — Thu, 20 May 2010 16:18:36 +0000

Sir,
May I ask u that,
At 5th step u’ve declared,’Private connStr as string ….’ But at 7th step u’ve added another one ‘Private connStr2 as string …’, Why?
At 5th step you’ve made some ‘code’ to ‘comment’.Then what is the use of ‘Function …’ procedure?
I need your help.

By: linglom

linglom — Thu, 20 May 2010 14:02:10 +0000

Hi, Doug
If there is nothing shows on the datagrid, you should check if there is any exception show on the output console window.

By: Dipta

Dipta — Wed, 19 May 2010 15:58:54 +0000

Thank you TEACHER.

By: Doug

Doug — Mon, 17 May 2010 04:48:24 +0000

Hi I tried this in vb2010 express and nothing pops up in datagridview any suggestions??

By: Bernard

Bernard — Wed, 21 Apr 2010 22:39:05 +0000

Thanks Man, Good work…..

By: nono

nono — Tue, 16 Feb 2010 10:24:07 +0000

That is great help, it does the trick,
I’ve added :

Chart1.Series.Clear()

in oder to get read of the “Series1″ which was defaulting.

Thank very much for this, very usefull.

By: linglom

linglom — Tue, 16 Feb 2010 02:46:36 +0000

Hi, Haxorz
The error message should tells exactly which namespace is not valid. It could be MySQL.Data, have you add the reference?