Get data to dataGrid from mysql - mysql

Question

How do i add data to dataGrid view in VB.net (I'm using WPF dataGrid).
Here is a code that works, this code is for login, my application can access database and i can manipulate data:
Public Function login(ByVal username As String, ByVal password As String)
Try
ManageConnection(False) 'Open connection'
Dim strQuery As String = "SELECT * FROM `dbns`.`wrks` WHERE `username` = '" + username + "' and password = '" + password + "'"
Dim SqlCmd As New MySqlCommand(strQuery, dbCon)
Dim reader As MySqlDataReader = SqlCmd.ExecuteReader()
If reader.HasRows Then
Return True
Else
Return False
End If
reader.Close()
Catch ex As MySqlException
Console.WriteLine("Error: " & ex.ToString())
Finally
ManageConnection(True)
End Try
Return False
End Function
How would i implement a SELECT * FROM xxxxx WHERE xxxx and populate
<DataGrid x:Name="dataGrid" HorizontalAlignment="Left" Margin="376,167,0,0" VerticalAlignment="Top" Height="100" Width="645"/>
This is my Sub for opening and closing connection:
Public Sub ManageConnection(ByVal CloseConnection As Boolean)
Try
'Pripremanje konekcije i upita'
dbCon = New MySqlConnection("server=127.0.0.1;user id=root;password=*****;database=****")
If CloseConnection = False Then
If dbCon.State = ConnectionState.Closed Then _
dbCon.Open()
Else
dbCon.Close()
End If
Catch ex As Exception
MsgBox("Nije moguća konekcija na udaljenu bazu podataka, koristi drugu opciju.")
End Try
End Sub
I want to know if i can use my existing function for connecting to database for datagrid specific needs.
In example:
Public Function testniQuery()
Dim queryString As String =
"SELECT * FROM table"
Dim adapter As SqlDataAdapter = New SqlDataAdapter(
queryString, connection)
Dim customers As DataSet = New DataSet
adapter.Fill(customers, "Customers")
End Function

Answer 1

I do not know Visual Basic that well because I work with C# but the Common Library Runtime (CLR) makes it easier to understand both languages.
When you are connected to MySQL, run your query which you will use DataAdapter to get the data from the query.
The result of the query can be saved in a DataTable and you can easily bind the DataTable to the DataGrid.
So, you run one query and you can use that table persistently in your code.
I do this is C#.
Please bear with C# code. This is a method that will do it
public DataTable Login(string username, string password){
//"SELECT * FROM `dbns`.`wrks` WHERE `username` = '" + username + "' and password = '" + password + "'"
string query = "SELECT * FROM wrks WHERE username = #username AND password = #password";
DataTable table = new DataTable();
using (MySQlConnection connection = new MySQlConnection(connectionString))
{
using (MySqlDataAdapter adapter = new MySqlDataAdapter(query, connection))
{
adapter.SelectCommand.Parameters.AddWithValue("#username", username);
adapter.SelectCommand.Parameters.AddWithValue("#password", password);
adapter.Fill(table);
return table;
}
}
}
The DataTable returned can then be binded to the DataGrid as shown below:
dataGrid1.DataSource = Login("username", "password").DefaultView;
dataGrid1.DataBind();