Question

currently i’m studying MySQL, sorry for my newbie question. Here my question

I have 2 class, the first one is Windows Form, and the other is just a class which I want contain all processes from SQL. here’s my code in SQL Class

public void SampleQuery(string tablename)
    {
        DataTable dataTable;

        string query = "SELECT * FROM " + tablename;

        //Open connection
        if (this.OpenConnection() == true)
        {
            adapter = new MySqlDataAdapter(query,connection);

            dataTable =  new DataTable();
            adapter.Fill(dataTable);

            //close Connection
            this.CloseConnection();
            return;
        }

What I want to do is, show the data from SQL with DataGridView.
Is it possible to code the datagridview in SQL Class above? or must be in Windows Form part?

if must be in windows form, how to throw the dataTable which is now hold all the data to Windows Form class?

thanks a lot for helping me. If my question sounds absurd just ask me.

Answer 1

You can use DataGrid DataSource property.

Sample code demontrate idea:

class MyForm : Form
{
   public MyForm()
   {
      InitializeComponent();
      DataAccess  dataAccess = new DataAccess();
      m_dataGrid.DataSource = DataAccess.SampleQuery("MyTable");
   }
}

class DataAccess 
{
   public DataTable SampleQuery(string tablename)
   {
      DataTable dataTable;
      // 
      // Your Code
      // ..
      return dataTable;
   }
}

I think is Form Load event handler is good place to load data (not constructor 😉 as i show above). You may olso implement some caching (load datatable each time if form is open is not efficient:))