I'm having a great deal of trouble finding code examples to connect a VB.net client application I am writing to a MYSQL5 database. I am trying to access a database I created through WAMP and phpMyAdmin.
where on the internet is a simple example of a programmatic implementation of an object I can use to connect these two seemingly un-connectable entities?
Just to make it a bit clearer:
I have a DB made through phpMyAdmin called: test
within the db is a table: sys_users
within the table are: user_ID (pk), user_name, user_password
simply looking to connect VB.net to test and query the table sys_users, returning a boolean if they exist. From there, I can figure out the rest of my solution for my program dealing with other tables and data.
thanks for any help in this.
Imports MySql.Data.MySqlClient
Imports System.Data.SqlClient
Public Class login
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
Dim strConStr As String = "Data Source=localhost;uid=********;pwd=********;database=********"
Dim conn As MySqlConnection
conn = New MySqlConnection(strConStr)
MsgBox(conn.ConnectionString.ToString)
Try
conn.Open()
MessageBox.Show("Connection Opened Successfully")
conn.Close()
Catch myerror As MySqlException
MessageBox.Show("Error Connecting to Database: " & myerror.Message)
Finally
conn.Dispose()
End Try
End Sub
End Class
Yes, this was a problem for someone else, but the solution seems to work so far. As for the Password validation etc, I will most definitely make use of it. All I needed guys, thanks.
Related
Hi all I'm having trouble with regards to opening my connection on my mysql database on xampp. I'm not quite sure about the issue here. But please do correct me if I'm wrong, is there a problem with my connectionstring script or does Visual Studio 2019 handle it differently now compared to it's previous versions. I've tried removing the "con.Open()" line. but the problem with this is I can't seem to even be able to insert some data into my databse without the "con.Open()" line
here's the code by the way.
Module Module1
Public con As New MySqlConnection
Public cmd As New MySqlCommand
Sub openCon()
con.ConnectionString = "server=localhost; username=admin; password=; database=db_tutorial"
con.Open()
End Sub
End Module
here's an image of the error by the way.
Look, I'm working and doing tests with Access databases in Visual Basic.
I created an access database, and place it in the bin / debug folder of the project. Without assigning a password , it connects sucesfully with the database ... but when I encrypt the database (or put a password to the database with exclusively mode), my connection fails:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim tabla As DataTable = New DataTable
Dim ds As DataSet = New DataSet
Dim conexion As New OleDb.OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=soq.accdb;Persist Security Info=False;Jet OLEDB:Database Password=mypassword;")
Try
conexion.Open()
MsgBox("Estoy operando.")
Catch ex As Exception
MsgBox("No ando haciendo eso")
End Try
conexion.Close()
End Sub
Whats the problem here?? I wrote something wrong??? (I got Microsoft Access 2013)
Okay guys, i found the solution!
The encryption method of Microsoft Access 2013 dont works properly. So my solution was simple: Use the encryption method of the 2007 version, and done!
Thanks all!
I have been working on this for hours I am sure it is something simple I am missing. I have a remote server that gets updated form from another pc once the sever gets updated I would like my PC to get the changes from the server I cant seem to get it done the closest I have been is shown below any help would be greatly appreciated. Connection string no issue just trying to update the PC database to Match the server database
Sub updateRecord()
Try
Dim dbConnection As New MySqlConnection("server=" & My.Settings.ServerIPAddress & ";user id=root;password=T#ttleT#le102;persistsecurityinfo=True;database=pmdatabase")
dbConnection.Open()
Using Adapter As New MySqlDataAdapter("Select * From tblpmdata", dbConnection)
Using Table As New DataTable
Adapter.Fill(Table) 'test to see if table is correct
Adapter.Fill(Me.PmdatabaseDataSet.tblpmdata)
Me.PmdatabaseDataSet.AcceptChanges()
Me.TableAdapterManager.UpdateAll(Me.PmdatabaseDataSet)
MsgBox(Table.Rows.Count)only shows 5 records when the server has 8 records
End Using
End Using
dbConnection.Close()
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
End Sub
I want to create a textbox which contents are validated every time the text in it changes. And an image is displayed beside the textbox if it is correct and another image shows up if its not correct. Pretty much like ajax.
Heres the method which I called from the class.
Public Sub read1()
cmd.CommandText = "SELECT * FROM testdb WHERE Name='" & name & "'"
Try
rdr = cmd.ExecuteReader
Dim n As String
If rdr.HasRows Then
n = rdr("Name").ToString
Form1.PictureBox1.Image = Image.FromFile("C:\wamp\www\Dropbox\Public\Check-icon.png")
Else
Form1.PictureBox1.Image = Image.FromFile("C:\wamp\www\Dropbox\Public\Delete-icon.png")
End If
Catch ex As Exception
And here the event which calls for the method:
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
x.name = TextBox1.Text
x.read1()
End Sub
End Try
End Sub
Problem is, the method seems to be only called once. And the first image that was displayed stays the same even after inputting a data which does not exist in the database.
I'm connecting this program to a mysql database using odbc. Can you help me determine whats the problem and how to fix it?
Heres the screenshot:
With a DataReader object, you have to call the Read method before you can access the row. I think it would need to look like the following. I am guessing at the VB.Net syntax and method name, but I am reasonably sure it would be simply rdr.Read.
If rdr.HasRows Then
rdr.Read
n = rdr("Name").ToString
Edit In addition, you probably need to close the DataReader. Some .NET data providers allow only a single reader to be open at a time on a given connection, and it seems likely that the ODBC provider is one of them. Without a specific call to close it, you would be relying on the garbage collector to clean it up:
rdr.Close
And while this has nothing to do with the question directly, you should probably use a parameterized query to avoid an SQL injection attack.
I have a project in Visual Studio 2008 and there is a working data connection to a MySQL database. In other words, I can query the db directly from Visual Studio and it will display the results.
I've tried a couple of approaches that I found online for writing a connection string and accessing the db, but no luck yet.
All I'm trying to do is code a button to query the db and then reset the text property of a label/textbox to display the results based upon another label/textbox value.
The pseudo-code I am imagining is something like this:
Private Sub query_submit_button_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles query_submit_button.Click
result_textbox.Text = SELECT field FROM table WHERE otherfield = key_textbox.Text
End Sub
I didn't see any related questions posted on SO - forgive me if I missed one that already exists and this is a dupe.
What is the correct way to accomplish this?
EDIT
Using MySQL 5.1
You can download the ODBC Provider and then reference, import, and use it to query the database through a ODBCCommand instance.
'Put this at the very top of your .VB file...
Imports System.Data.ODBC
'Put this in some method in your code when you are ready to query the DB...
Using connection As New OdbcConnection(connectionString)
Dim command As New OdbcCommand(strSqlQuery, connection)
connection.Open()
result_textbox.Text = command.ExecuteScalar.ToString
End Using
i used DaMartyr's answer to get 99% there, but needed to add this declaration:
Dim connectionString As String = "driver={MySQL ODBC 5.1 Driver};server=SERVER;uid=USERID;pwd=PASSWORD;database=DATABASE"
just replace the SERVER, USERID, PASSWORD, & DATABASE with your personal settings